Devices and methods for retrievable intra-atrial implants

ABSTRACT

Devices and methods to enhance the implantation, retreivability, or repositionability are provided. Embodiments of devices include pivotable sections providing the ability to maintain the device&#39;s engagement with a delivery system during implantation where the deliver system approaches an opening of the septum at an angle. Embodiments of devices also include configurations that allow for improved retrieval into a delivery system in the event that a malfunction or a problem with the patients physiology is detected.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation-in-part of U.S. patent applicationSer. No. 13/167,502, filed Jun. 23, 2011, which claims the benefit ofU.S. Provisional Appl. No. 61/449,566, filed Mar. 4, 2011, and is acontinuation-in-part of U.S. patent application Ser. No. 12/954,468,filed on Nov. 24, 2010, now U.S. Pat. No. 8,752,258, which is acontinuation-in-part of U.S. patent application Ser. No. 12/719,843,filed on Mar. 8, 2010, now U.S. Pat. No. 8,157,860, and claims thebenefit of U.S. Provisional Application No. 61/299,559, filed on Jan.29, 2010. U.S. patent application Ser. No. 12/719,843 claims the benefitof U.S. Provisional Application No. 61/240,085 filed Sep. 4, 2009. Thisapplication is also a continuation-in-part of U.S. patent applicationSer. No. 13/290,295, filed on Nov. 7, 2011, now U.S. Pat. No. 8,460,372.U.S. application Ser. No. 13/167,502, filed Jun. 23, 2011 is also acontinuation-in-part of U.S. patent application Ser. No. 12/954,541,filed Nov. 24, 2010, now U.S. Pat. No. 8,740,962. Each application isherein incorporated by reference in its entirety.

INCORPORATION BY REFERENCE

This application incorporates by reference the following applications:U.S. patent application Ser. No. 12/447,617 filed Apr. 28, 2009;International Patent Application No. PCT/AU2007/001704 filed Nov. 7,2007; and Australian Patent Application No. AU 2006906202 filed Nov. 7,2006.

FIELD OF THE INVENTION

The present invention relates generally to devices and methods fortreating heart failure. In particular, the invention relates tointeratrial pressure vents, shunts and the like, which reduce elevatedpressure on one side of the heart thus mitigating the symptoms thatresult, as well as placement devices, systems, and methods therefore.

BACKGROUND

The functioning of the heart and the opening and closing of heart valvesoccur primarily as a result of pressure differences. For example, theopening and closing of the mitral valve between the left atrium and theleft ventricle occurs as a result of the pressure differences betweenthe left atrium and the left ventricle. During ventricular diastole(ventricular filling), when ventricles are relaxed, the venous return ofblood from the pulmonary veins into the left atrium causes the pressurein the atrium to exceed that in the ventricle. As a result, the mitralvalve opens, allowing blood to enter the ventricle. As the ventriclecontracts during ventricular systole (ventricular emptying), theintraventricular pressure rises above the pressure in the atrium andpushes the mitral valve shut. Blood then is pumped from the ventriclesto the arteries.

The heart has four valves to ensure that blood does not flow in thewrong direction during the cardiac cycle; that is, to ensure that theblood does not back flow from the ventricles into the correspondingatria, or back flow from the arteries into the corresponding ventricles.The valve between the left atrium and the left ventricle is the mitralvalve. The valve between the right atrium and the right ventricle is thetricuspid valve. The pulmonary valve is at the opening of the pulmonaryartery. The aortic valve is at the opening of the aorta.

Blood flowing back from the left ventricle into the left atrium, orsystolic dysfunction of the left ventricle and valve disease, asmentioned in the background, may cause high atrial pressure and reducethe flow of blood into the left atrium from the lungs. As blood backs upinto the pulmonary system, fluid leaks into the lungs and causespulmonary edema. Blood volume going to the atrium reduces volume ofblood going forward into the aorta causing low cardiac output. Excessblood in the atrium over-fills the ventricle during each cardiac cycleand causes volume overload in the left ventricle.

Heart failure with such symptoms is a common and potentially lethalcondition affecting humans, with sub-optimal clinical outcomes oftenresulting in symptoms, morbidity and/or mortality, despite maximalmedical treatment.

Congestive heart failure (CHF) is a condition affecting millions ofpeople worldwide. CHF results from a weakening or stiffening of theheart muscle that commonly is caused by myocardial ischemia (due to,e.g., myocardial infarction) or cardiomyopathy (e.g., myocarditis,amyloidosis). CHF causes a reduced cardiac output and inadequate bloodto meet the needs of body tissues.

Treatments for CHF include: (1) pharmacological treatments, (2)assisting systems, and (3) surgical treatments. Pharmacologicaltreatments, e.g., with diuretics, are used to reduce the workload of aheart by reducing the blood volume and preload. While pharmacologicaltreatments improve quality of life, they have little effect on survival.Assisting devices, e.g., mechanical pumps, are used to reduce the loadon the heart by performing all or part of the pumping function normallydone by the heart. However, in a chronic ischemic heart, a high-ratepacing may lead to increased diastolic pressures, calcium overload, anddamage to the muscle fibers. There are at least three surgicalprocedures for treating a heart failure: (1) heart transplant, (2)dynamic cardiomyoplasty, and (3) the Batista partial leftventriculectomy. These surgical treatments are invasive and have manylimitations.

CHF is generally classified into systolic heart failures (SHF) ordiastolic heart failures (DHF). In a SHF, the pumping action of a heartis reduced or weakened. A normal ejection fraction (EF), which is afunction of the volume of blood ejected out of the left ventricle(stroke volume) divided by the maximum volume remaining in the leftventricle at the end of a diastole or relaxation phase, is greater than50%. In a SHF, the EF is reduced to less than 50%. A patient with a SHFmay have an enlarged left ventricle because of cardiac remodelingdeveloped to maintain an adequate stroke-volume. This pathophysiologicalphenomenon is often associated with increased atrial pressure and leftventricular filling pressure.

DHF is a heart failure without any major valve disease even though thesystolic function of the left ventricle is preserved. Generally, DHF isa failure of the ventricle to adequately relax and expand, resulting ina decrease in the stroke volume of the heart. In particular, “diastolicheart failure” refers to the clinical syndrome of heart failureoccurring in the context of preserved left ventricular systolic function(ejection fraction) and in the absence of major valvular disease. Thiscondition is characterized by a stiff left ventricle with decreasedcompliance and impaired relaxation, which leads to increasedend-diastolic pressure. Approximately one third of patients with heartfailure have diastolic heart failure and there are very few, if any,proven effective treatments. Presently, there are very few treatmentoptions for patients suffering from DHF. DHF afflicts between 30% and70% of patients with CHF.

There are several known techniques used to treat symptoms of DHF.Without attempting to characterize the following references, forexample, U.S. Pat. No. 8,091,556 by Keren et al. discloses the use of aninteratrial pressure relief shunt with a valve and a tissue affixationelement at each end of the shunt; and United States Patent ApplicationPublication No. 20050165344 by Dobak discloses a pressure relief systemwith an interatrial septal conduit with an emboli barrier or trapmechanism to prevent cryptogenic stroke due to thrombi or embolicrossing the conduit into the left side circulation. Dobak alsodiscloses a conduit with a one-way valve that directs the blood flowfrom the left atrium to the right atrium.

The constantly evolving nature of heart failures represents asignificant challenge for developing an efficient treatment. Therefore,there is a need for novel and adaptable methods and devices for treatingDHF, for example, by creating a pressure relief shunt which can beretrieved, repositioned, adjusted, expanded, contracted, occluded,sealed and/or otherwise altered as required to treat a patient.

In the past, strategies have been described for the relief of highpressure in the right atrium, such as the creation of hole(s) in thenative or surgically created septum between the left and right atria.These have been designed for the rare conditions of pulmonaryhypertension or cavopulmonary connections for certain complex congenitalheart diseases. Accordingly, there still exists a need for devices andmethods to treat heart failure, particularly diastolic and/or systolicfailure of the left ventricle and its consequences.

BRIEF SUMMARY

Embodiments of the present invention include an implantable device,which can be referred to herein as a device, vent, venting device,stent, implantable, implantable device, valve, shunt, prosthesis,interatrial pressure vent, intercardiac pressure vents/devices, (theabove terms and synonyms of such terms will be used hereininterchangeably and shall have the same meaning unless an alternatemeaning is made explicitly clear). In some embodiments, the implantabledevice may comprise may comprise a body assembly. In embodiments, thebody assembly refers to the primary structural portion of the devicewhich may comprise, or otherwise itself be, what is referred to hereinas a core segment. In embodiments, optionally a flow control element isincluded. A flow control element is sometimes referred to as a valve.Not all embodiments comprise a flow control element or the like, andthose skilled in the art will appreciate that even embodiments describedin connection with a flow control element need not necessarily contain aflow control element or the like. To that end, the designs, methods,configurations of components, etc. disclosed herein have been describedalong with various configurations. For example, embodiments may bedescribed which include flow control elements or features of theimplantable device; however, those skilled in the art will appreciatewhere the designs, components, configurations or components describedherein can be used in combination, or interchangeably, and that thedescription herein does not limit such interchangeability or combinationof components to only that which is described herein.

The present invention provides implantable devices for treating heartconditions in a patient. The device may have a first elongated, orcollapsed, profile for percutaneously delivery and a second expandedprofile upon deployed from the delivery catheter. The device may have ahub or other attachment mechanism that is adapted to cooperate with acomplementary mechanism on a deployment and/or retrieval device. In someembodiments, this hub or other attachment device is located at an apexof the implantable device. In some instances, the hub or otherattachment device is comprised of a cardiac-environment compatiblemachinable material.

The device may comprise a proximal flange, a distal flange, a coresegment, and a hub. Each of the proximal and distal flanges may comprisea plurality of flange segments each with a first end and a second end.In some embodiments, the proximal flange comprises a proximal curvyportion, which allows the device to curve, turn, bend or twist. The coresegment defines a passage which is adapted to permit fluid to flowtherethrough from one side of said septal wall to another side of saidseptal wall. In some embodiments, the second ends of the first flangeand the second ends of the second flange are contiguous with the coresegment. In some embodiments, the core segment has a first diameter whendeployed. The hub may be configured to releasably attach to a deliverycatheter. In some embodiments, the first end of the proximal flange isconfigured to rotate against the hub.

In some embodiments, the implanted device may be removed after being (a)fully deployed and disengaged from its delivery system (such as acatheter delivery system including the type described herein) and/or (b)within, near, or implanted in the targeted anatomy of the subject. Insome embodiments, the device may be repositioned from being partially orfully deployed at one location to a being deployed at another location.

In some embodiments, the device comprises a plurality of struts, a hubthat is connected to an end of at least one of the struts, at leastthree pluralities of fork sections each having two or more prongs, afirst flange that is formed at least in part from a first set of forkprong junctions, a second flange that is formed at least in part from asecond set of fork prong junctions, and a core segment. The device maybe configured to be collapsible about its longitudinal axis so that thedevice may be stored in a delivery apparatus for percutaneous deliveryto a hole in the septal wall of a patient's heart and to be expandableupon deployment so that it takes on its pre-collapsed shape. In someembodiments of the present invention, the hub and the struts of thedevice form an apex at the proximal end of the device.

In some embodiments, the device includes a hub and a first portion whichis operably connected to the hub. The first portion comprises acontinuous, metal sheet material which has a plurality of contiguousprimary strands each of which branches into at least two secondarystrands. The first portion has at least a first flange section, a secondflange section, and a core segment and is configured such that at leastpart of the core segment is positioned between the first and secondflange sections. In such embodiments, the device is adapted to bedelivered by a catheter into the patient's heart such that the deviceexpands during the delivery to an expanded configuration, and the deviceis further adapted to be collapsed from its expanded configuration bywithdrawing the device back into the catheter.

In some embodiments, the device comprises a plurality of interconnectedunits, a hub that is connected to the near end of at least one of theunits, a first flange that is at least in part formed by the junctionsof arm sections of adjacent units, a second flange that is at least inpart formed by the far ends of at least some of the units, and a coresegment. Each of the units includes a first diamond section connected atits far end to the near end of a second diamond section. Each of theunits is connected together by way of its arm sections, which extendfrom the first diamond section of the unit, and by interconnections oftheir respective second diamond sections. The device is configured to becollapsible about its longitudinal axis so that the device may be storedin a delivery apparatus for percutaneous deliver to a hole in the septalwall of a patient's heart. Like other embodiments described herein, thedevice is expandable upon deployment and will take on its pre-collapsedshape. The hub and the units in some instances form an apex at whatwould be the near end of the device which is within right atrium of thepatient's heart when implanted.

In some other embodiments, the device comprises a plurality of struts, ahub that is connected to an end of at least one of the struts, at leasttwo pluralities of fork sections each having two prongs, a first flangethat is formed from at least two of the struts, a second flange that isformed at least in part of at least two of a set of fork prongjunctions, and a core segment.

The present invention also includes techniques, systems, and methods fordeployment of the devices described herein.

In some embodiments, the device comprises a core segment, which maycomprise a self expanding mesh. In embodiments the device may becollapsible so as to fit into a placement catheter described herein. Insome embodiments, the device may be both self-explaining andcollapsible.

Some embodiments include a delivery system for the implantable device.The delivery system may comprise a delivery sheath and a deliverycatheter. The delivery sheath may have a distal end, a proximal end, anda center lumen-like cavity. The delivery catheter may be slidablydisposed within the center lumen-like cavity. The distal end of thedelivery catheter distal end of the delivery catheter may be configuredto releasably attach to an implantable device.

In some embodiments, the implantable device is designed to safeguardagainst portions of the flange that are to engage the proximal side ofthe septum from entering into the portion of the heart that is on thedistal side of the septum. This safeguard is best understood byconsidering the implantable device in its state of collapse along itslongitudinal axis for percutaneous delivery to the patient's heart. Thesafeguard is to provide a minimum longitudinal distance between thedistal end of the proximal flange and the distal end of the core segmentof the implantable device. This longitudinal distance is to be thequotient of the longitudinal length of the septal aperture into whichthe device is expected to be implanted divided by the cosine of theangle the longitudinal axis of the device is expected to make duringdelivery in relation to the longitudinal axis of the septal aperture.Due to the dynamic nature of the heart and the delivery apparatus duringthe deployment of the device, in some instances this minimum distance isincreased by a factor ranging between 1.1 and 2.0.

The body assembly may be constructed from preformed wire braid. The wirebraid may be formed from nitinol with a martensite/austenite transitiontemperature is below 37° C. so it remains in its superelastic,austenitic phase during use. The transition temperature is below about25+/−5° C. The wire should have a diameter of at least about 0.0035(about 2 lbs of breaking strength at 200 ksi tensile). The wire shouldhave a very smooth surface to reduce thrombogenicity or irritationresponse from the tissue. The surface finish may be 63 μin RA or better.This surface may be obtained either by mechanical polishing, byelectropolishing or a combination. In embodiments, the surface may becleaned with detergents, acids and/or solvents to remove residual oilsor contamination and then controllably passivated to insure minimalcorrosion.

The implantable device, or a part thereof, e.g., the body portion, maybe formed from grade 1 or grade 6 titanium. In embodiments, the body maybe formed of grade 9 titanium. In embodiments, the body may be formed of316L stainless steel. In embodiments, the body may be formed of 416Lstainless steel. In embodiments, the body may be formed of nitinol orcobalt-chromium-nickel alloy (such as Elgiloy®). In embodiments, thebody is formed of platinum iridium. In embodiments, the body may beformed of a cobalt chromium alloy. In embodiments, the body may beformed of MP35N®. In embodiments, the body may be formed of Vitalium™.In embodiments, the body may be formed of Ticonium™. In embodiments, thebody may be formed of Stellite®. In embodiments, the body may be formedof tantalum. In embodiments, the body may be formed of platinum.Materials disclosed with reference to the body or any component of thedevice disclosed herein are not meant to be limiting. The skilledartisan will appreciate that other suitable materials may be used forthe body or any other component of the device.

In embodiments, the body assembly may be formed from a length ofcylindrical tubing that is precut with slots at specific locations andthen formed in a series of processes to produce a shape suited for thepurpose of containing a flow control element within the interatrialseptum.

As an example, a first process might be to stretch the cylinder toexpand its internal diameter to a uniform target dimension. This can bedone with a balloon or a standard tubing expander consisting of asegmented sleeve and tapered conical inserts that increase the diameterof the sleeve when the cones are advanced toward the center. In orderthat the shape of the stretched tubing be preserved, the cylinder shouldbe annealed while held into this stretched shape by heating it beyond300° to 600° for at least about 20 minutes to allow the internalstresses to be relieved. A second process might be to form one flangeend shape using a similar process as the first process but using a toolshape specially designed for the first flange shape. A third processmight be to form the second flange end shape using a similar process asthe first process but using a tool specially designed for the thirdflange shape. These shapes must be annealed using a similar process asthe first shape, either in separate steps or altogether.

In some embodiments of the device, pre-selected areas of the sheetmaterial of which device is comprised have reduced through-thicknessesin relation to the through-thickness of sheet material of other areas ofthe implantable device. These areas of reduced through-thickness areselected based upon a desire to provide these areas with greaterflexibility. In some method embodiments, a device having reducedthrough-thickness in preselected areas is made by a process in which atube of a particular wall thickness is machined in preselected areas tolocally reduce the through-thickness of the tube, and then apre-selected pattern is cut into the machined tube to form a patternedtube which is then thermomechanically formed into the shape the deviceis to have in use after implantation. Such variations of thickness maybe used on any portions of embodiments of the device disclosed hereinwhere variations in flexibility are desirable.

In embodiments, the internal diameter of the finished interatrialpressure vent is larger than about 5 mm to enable adequate venting ofthe left atrium and minimize damage to blood components from excessiveshear stress, but enabling the interatrial pressure vent to stow in aplacement catheter of smaller than about 14 F.

In embodiments, the flow control element opening is at least about 50sq. mm. In embodiments, the flow control element opening is 50 sq.mm+−10 sq. mm. In another embodiment, the cylindrical section is formedwith an inside diameter of between 3 and 15 mm.

The internal diameter of the body segment may be a constant dimensionalong the center, longitudinal axis of the interatrial pressure vent andis long enough to isolate the flow control element from deflection ordamage as a result of contact with other structural elements of theheart.

In embodiments, the body segment is formed into a substantially toroidalshape, the inner diameter tapering down and then up again from one sideof the implant to the other. In embodiments, the length of the bodysection may be about 4 mm. In embodiments, the length of the bodysection may be between about 3 mm and about 40 mm.

Other embodiments and advantages of the invention will become moreapparent from the following detailed description when taken inconjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention will become more fully apparent from the followingdescription and appended claims, taken in conjunction with theaccompanying figures. Understanding that these figures merely depictexemplary embodiments, they are, therefore, not to be consideredlimiting. It will be readily appreciated that the components of thepresent invention, as generally described and illustrated in the figuresherein, could be arranged and designed in a wide variety of differentconfigurations. Nonetheless, embodiments will be described and explainedwith additional specificity and detail through the use of theaccompanying figures in which:

FIG. 1 is a schematic cross-sectional view of a patient's heart with aninteratrial pressure vent in situ;

FIG. 2 is an end view of the interatrial pressure vent of FIG. 1 in situas seen along line 2-2 of FIG. 1;

FIG. 2A is an end-on close up view of a flange segment of an embodiment;

FIG. 2B is an enlarged side cross-sectional view of an embodiment toillustrate variations in flexibility in a flange;

FIG. 3 is a cross-sectional side view taken along line 3-3 of FIG. 2;

FIG. 4 is perspective view of the interatrial pressure vent by itself;

FIG. 5 is a right side view of implantable device of FIG. 4;

FIG. 6 is a distal end view of the implantable device of FIG. 4;

FIG. 7 is an enlarged fragmentary cross-sectional view taken along line7-7 of FIG. 6;

FIGS. 7A through 7C are a side elevational views of embodiments of thedevice in the stowed position;

FIG. 8 is a side elevational view of the interatrial pressure vent ofFIG. 1 in a collapsed configuration prior to loading in a placementcatheter;

FIG. 9 is a side view of the distal end of a placement catheter in itsopen position;

FIG. 10 is a side view of the distal end of a placement catheter in itsopen position and with an interatrial pressure vent in its stowedconfiguration and in position over the inner shaft of the catheter;

FIG. 11 is a side view of the distal end of a placement catheter in aclosed configuration with an interatrial pressure vent in its stowedconfiguration loaded onto the placement catheter;

FIG. 11A is a side view of another embodiment of a placement catheterwith an interatrial pressure vent stowed therein;

FIG. 12 is an exploded perspective view of the proximal and distal endsof a placement catheter;

FIG. 13 is a cutaway view of a heart of a patient and the distal end ofa placement catheter in position across the interatrial septum;

FIG. 14 is a schematic cross sectional side view of the proximal anddistal end of a placement catheter in a closed position and positionedacross the interatrial septum of the heart of a patient;

FIG. 15 is a view similar to FIG. 14 but showing the distal end of theplacement catheter in a partially open position and the distal flangesegments of the interatrial pressure vent deployed;

FIG. 16 is a view similar to FIG. 15 but showing the distal flangesegments of the interatrial pressure vent in position against the wallof the interatrial septum;

FIG. 17 is an enlarged cross-sectional detail view of the distal end ofthe placement catheter of FIG. 16 but showing the distal flange segmentsof the interatrial pressure vent being retracted from the interatrialseptum as if it were determined to be in an undesirable position byimaging the radiopaque markers and going to be redeployed;

FIG. 18 is a view similar to FIG. 16 but showing further deployment ofthe interatrial pressure vent by releasing the proximal flange segmentsif imaging determines a correct positioning of the distal flangesegments;

FIG. 19 is an enlarged cross-sectional detail view of the placementcatheter of FIG. 18 but showing the interatrial pressure vent fullyreleased in position and the placement catheter being removed;

FIG. 19A is schematic depiction of another embodiment of a placementcatheter system and interatrial pressure device along with thedeployment process therefor;

FIG. 19B is schematic depiction of another embodiment of a placementcatheter system and deployment process therefor;

FIG. 20 is a side elevational view of an alternate embodiment of aninteratrial pressure vent body with slanted flange segment ends;

FIG. 21 is a side elevational view of an alternate embodiment of aninteratrial pressure vent body with staggered flange segment ends;

FIG. 22 is a perspective view of an alternate embodiment of aninteratrial pressure vent body with an integrated retrieval means andthrombus clot strain;

FIG. 23 is a right side view of the body assembly of FIG. 22;

FIG. 24 is an end view of an alternate embodiment of interatrialpressure vent;

FIG. 25 is a cross-sectional side view taken along line 25-25 of FIG.24;

FIG. 26 shows and alternate embodiment wherein the core segment 106 isovular rather than circular and thus the core segment is a cylindroid orelliptic cylinder rather than a simple cylinder;

FIG. 27 is schematic depiction of another embodiment of a placementcatheter system and interatrial pressure device along with thedeployment process therefor;

FIG. 27A is a side elevational view of the embodiment described inconnection with FIG. 27 in the stowed position;

FIGS. 28A through 28C depict other embodiments of the device that directthe flow of blood in a desired direction;

FIGS. 29A, 29B and 29C are end-on views from the RA side of the heartseptum showing three different embodiments of exit profiles of the flowcontrol element;

FIG. 30 is a side view of an embodiment of the device having a tube-likeextension into the RA side of the heart;

FIG. 31 depicts an exploded view of a first embodiment of a mounting andloading tool for mounting and loading a prosthesis;

FIG. 32 depicts an exploded view of a second embodiment of a mountingtool for mounting a prosthesis;

FIGS. 33 and 34 depict the mounting tool with a prosthesis mounted;

FIG. 35 depicts an exploded view of a loading tool for loading aprosthesis on a mounting tool onto a delivery device;

FIG. 36 depicts the prosthesis being loaded into a catheter;

FIG. 37 depicts the loaded catheter with protective packaging;

FIGS. 38A and 38B depict an additional embodiment of a control device orhandle for deploying the prosthesis;

FIGS. 39A through 39E depict another embodiment of a control device fordeploying the prosthesis;

FIG. 40 depicts another embodiment of a control device or handle;

FIG. 41 depicts a retrieval device useful for retrieving a deployedprosthesis;

FIG. 42 depicts the retrieval device of FIG. 41 with a retrieval basketdeployed;

FIG. 43 depicts a closer view of the basket of FIG. 42;

FIGS. 44 and 45 depict retrieval devices using dilators; and

FIGS. 46-49 depict additional embodiments of an implantable prosthesiswith retrieval and redeployment features.

FIG. 50 depicts anatomy of a human being and a human heart, withparticular focus on the pathways and natural lumens of the body;

FIG. 51 depicts a closer view of a heart and how guide wires andcatheters may be maneuvered in and around the heart to deployembodiments;

FIG. 52 depicts a first catheter extending from the superior vena cavato the coronary sinus of the heart;

FIG. 53 depicts an ablative catheter in the coronary sinus for creatingan opening into the left atrium of the heart;

FIG. 54 depicts the ablative catheter creating the opening;

FIG. 55 depicts a balloon catheter for expanding the opening;

FIG. 56 depicts an embodiment for an implantable device used forcoronary sinus pressure relief, the device being in a non-deployedstate;

FIG. 57 depicts the stent of FIG. 56 in a deployed state;

FIG. 58 depicts a first embodiment of a flange for the atrial wall;

FIG. 59 depicts a second embodiment of a flange for the atrial wall;

FIG. 60 depicts another embodiment of a stent suitable for ensuringcommunication between the right atrium and the coronary sinus;

FIG. 61 depicts details of a stent with a one-way valve; and

FIGS. 62A and 62B depict another embodiment of a stent.

FIG. 63 depicts an embodiment of an implantable device implanted in theatrial septum.

FIG. 64 depicts an embodiment of an implantable device in its lowprofile configuration.

FIG. 65 depicts an expanded embodiment of an implantable device.

FIG. 66 depicts a partially deployed implantable device embodiment.

FIG. 67 depicts a cross-sectional view of a device implanted in anatrial septum.

FIG. 68 depicts an expanded embodiment of an implantable device.

FIG. 69 depicts an elevational view of a expanded device embodiment.

FIG. 70A depicts a means by which a hub of a device may connect to acatheter.

FIG. 70B depicts a cross-section of the means of FIG. 70A.

FIG. 71A depicts another means by which a hub of a device may connect toa catheter.

FIG. 71B depicts a cross-section of the means of FIG. 71A.

FIG. 72A depicts yet another means by which a hub of a device mayconnect to a catheter.

FIG. 72B depicts a cross-section of the means of FIG. 72A.

FIG. 73A depicts another means by which a hub of a device may connect toa catheter.

FIG. 73B depicts a cross-section of the means of FIG. 73A.

FIG. 74A depicts yet another means by which a hub of a device mayconnect to a catheter.

FIG. 74B depicts a cross-section of the means of FIG. 74A.

FIG. 75A depicts another means by which the hub of the device mayconnect to a catheter.

FIG. 75B depicts the means of FIG. 75A in a connected state.

FIG. 75C depicts a cross-section of the means of FIG. 75B.

FIG. 76 depicts a cross-section of the proximal end of a deviceembodiment.

FIG. 77 depicts a side view of the proximal end of a device embodimentin which the hub has posts to which the flange segments are attached.

FIGS. 78A-78F depict an insertion sequence of a device embodiment intoan atrial septum.

FIG. 79 depicts a device embodiment being deployed at an angle into anorifice in an atrial septum.

FIG. 80A depicts a perspective view of a device embodiment.

FIG. 80B depicts an elevational side view of the device of FIG. 80A.

FIG. 80C depicts a top view of the device of FIG. 80A.

FIG. 80D depicts the device of FIG. 80A having been cut and rolled outinto a plane to show its cutting pattern.

FIG. 80E depicts a cross-section of a strut of the device of FIG. 80Dtaken across cutting plane 80E-80E.

FIG. 81A depicts an elevational view of a device embodiment.

FIG. 81B depicts a top view of the device of FIG. 81A.

FIG. 81C depicts the device of FIG. 80A having been cut and rolled outinto a plane to show its cutting pattern.

FIG. 81D depicts a cross-section of a strut of the device of FIG. 81Ctaken across cutting plane 81D-81D.

FIGS. 82A-D depict the insertion of a device embodiment into an atrialseptum.

FIG. 83A depicts a perspective view of a device embodiment.

FIG. 83B depicts the device of FIG. 83A having been cut and rolled outinto a plane to show its cutting pattern.

FIG. 83C depicts a cross-section of a strut of the device of FIG. 83Btaken across cutting plane 83E-83E.

DETAILED DESCRIPTION

Certain specific details are set forth in the following description andFigures to provide an understanding of various embodiments. Those ofordinary skill in the relevant art will understand that they canpractice other embodiments without one or more of the details describedbelow. Further, while various processes are described herein withreference to steps and sequences, the steps and sequences of steps arenot be understood as being required to practice all embodiments of thepresent invention.

Unless otherwise defined, explicitly or implicitly by usage herein, alltechnical and scientific terms used herein have the same meaning asthose which are commonly understood by one of ordinary skill in the artto which this present invention pertains. Methods and materials similaror equivalent to those described herein may be used in the practice ortesting of the present invention. In case of conflict between a commonmeaning and a definition presented in this document, latter definitionwill control. The materials, methods, and examples presented herein areillustrative only and not intended to be limiting.

Certain specific details are set forth in the following description andFigures to provide an understanding of various embodiments. Those ofordinary skill in the relevant art will understand that they canpractice other embodiments without one or more of the details describedbelow. Further, while various processes are described herein withreference to steps and sequences, the steps and sequences of steps arenot be understood as being required to practice all embodiments of thepresent invention.

Unless expressly stated otherwise, the term “embodiment” as used hereinrefers to an embodiment of the present invention.

Unless a different point of reference is clear from the context in whichthey are used, the point of reference for the terms “proximal” and“distal” is to be understood as being the position of a practician whowould be implanting, is implanting, or had implanted a device into apatient's atrial septum from the right atrium side of a patient's heart.An example of a context when a different point of reference is impliedis when the description involves radial distances away from thelongitudinal axis or center of a device, in which case the point ofreference is the longitudinal axis or center so that “proximal” refersto locations which are nearer to the longitudinal axis or center and“distal” to locations which are more distant from the longitudinal axisor center.

As used herein, the terms “subject” and “patient” refer to any animal,such as a mammal like livestock, pets, or humans. Specific examples of“subjects” and “patients” include, but are not limited, to individualsrequiring medical assistance, and in particular, requiring treatment forsymptoms of heart failure.

As used herein, the term “pressure differential” means the difference inpressure between two points or selected spaces; for example between oneside of a flow control element and another side of the flow controlelement.

As used herein, the term “embolic particle” means any solid, semi-solid,or undissolved material, that can be carried by the blood and causedisruption to blood flow when impacted in small blood vessels, includingthrombi.

As used herein, the terms “radially outward” and “radially away” meansany direction which is not parallel with the central axis. For example,considering a cylinder, a radial outward member could be a piece of wireor a loop of wire that is attached or otherwise operatively coupled tothe cylinder that is oriented at some angle greater than 0 relative tothe center longitudinal axis of the cylinder.

As used herein, the term “axial thickness” means the thickness along anaxis parallel to the center longitudinal axis of a shape or component.

As used herein, the term “axial direction” means direction parallel tothe center longitudinal axis of a shape or component.

As used herein, a “sealable connection” is an area where componentsand/or objects meet wherein the connection defines provides for aninsubstantial leakage of fluid or blood through the subject area.

As used herein, the term “lumen” means a canal, duct, generally tubularspace or cavity in the body of a subject, including veins, arteries,blood vessels, capillaries, intestines, and the like.

As used herein, the term “sealably secured” or “sealably connected”means stably interfaced in a manner that is substantially resistant tomovement and provides resistance to the flow of fluid through or aroundthe interface.

As used herein, the term “whole multiple” means the product contains nodecimal.

It is to be understood that whenever relational numbers are used herein,e.g., “first,” “second,” etc., they are used for convenience ofdescription and so they are to be interpreted with regard to theparticular embodiment or claim in which they are presented, rather thanas applying globally throughout this document to all embodiments or allclaims. Thus, for example, in one embodiment it may be more convenientto use the term “first flange” to describe a flange that would belocated in the right atrium when the device of that embodiment isimplanted in an atrial septum, whereas it might be more convenient touse the term “first flange” in another embodiment to refer to refer to aflange that would be located in the left atrium when the implantabledevice of that embodiment is implanted.

The present invention provides structures that enable several uniqueintracardiac and intraluminal valve devices, loaders, controls andplacement devices and catheters therefor. In some embodiments directedtoward the intra-cardiac setting, these valve devices are intended toallow sufficient flow from the left atrium to the right atrium torelieve elevated left atrial pressure and resulting patient symptoms butalso prevent the amount of flow from the right atrium to the left atriumto minimize the potential for thrombi or other embolic material fromentering the arterial circulation. For example, the device can be usedto regulate the pressure in a heart chamber. Specifically, the devicecan be used to treat elevated chamber pressures in a patient sufferingfrom CHF or having a Patent Foramen Ovale (PFO) or an Atrial SeptalDefect (ASD) that needs repair but is preferably left with residual flowbetween atria so as not to traumatize the heart hemodynamics but stillprevent embolization from the right to left atria.

However, it should be appreciated that embodiments are applicable foruse in other parts of the anatomy or for other indications. Forinstance, a device such as that described in this disclosure could beplaced between the coronary sinus and the left atrium for the sameindication. Also, a pressure vent such as is described in thisdisclosure could be placed between the azygous vein and the pulmonaryvein for the same indication.

The present invention may include a percutaneously deliverable device.In some embodiments, the device has a straightened, elongated,low-profile delivery configuration suitable for delivery via a deliverysystem. The device may have a generally radially expanded and sometimesshortened deployed profile. For example, it can have a distal expandedportion positioned on the left atrial side of the septum, a rightexpanded portion positioned on the right atrial side of the septum,and/or a shunt portion, sometimes referred to as a “core segment”,positioned through an aperture in the septum.

The present invention also provides attachment mechanisms betweenpercutaneous delivery systems and the implantable devices. Suchattachment mechanisms may allow the device to conform to the heartanatomy prior to and during deployment from the percutaneous deliverysystem, to be repositioned during deployment, and/or to be retrievedduring or repositioned after deployment.

The device may have a hub or other attachment mechanism that is adaptedto cooperate with a complementary mechanism on a deployment and/orretrieval apparatus. This hub or other attachment device may be locatedat an apex of the device. The hub or other attachment device maycomprise a cardiac-environment-compatible machinable material, e.g., astainless steel, a particular example of which being 316 LVM stainlesssteel.

Referring now to FIG. 1, one embodiment of an interatrial pressure ventis shown. FIG. 1 depicts the heart 1000 of a human subject. “LA” refersto the left atrium, and “RA” refers to the right atrium. The interatrialseptum is depicted as 107. The embodiment of the interatrial pressurevent 100 shown includes a body element 101 and flow control element 104,embodiments of which will be described in further detail below. The bodyelement 101 may comprise flanges 102 and 103. In this and otherembodiments described herein, flanges 102 and 103 may be annularflanges, which define a gap 2000 into which the septum 107 fits. Inembodiments, after insertion, the interatrial pressure vent is securelysituated in an opening created in the interatrial septum. Arrow F inFIG. 1 shows the direction of flow. It can be thus seen that a build upof pressure in the LA can be vented, by way of the inventive device, tothe RA.

As illustrated in FIG. 63, another embodiment of an implantable device6300 is deployed across the atrial septum 6302. The device 6300 includesan expanded distal flange 6304, a core segment 6306, an expandedproximal flange 6308, and a hub 6310. The distal flange 6304 is apposedto the septum 6302 on the left atrial side, and as will become moreapparent in reference to discussion and figures below, all flangesegments extend radially outward from the longitudinal axis of thedevice 6300. The core segment 6306 is placed through the aperture 6312on the septum 6302, connecting to the distal and proximal flanges 6304,6308. The core segment 6306 may be generally tubular, but also may be ofany suitable shape that allows blood communication between the leftatrium LA and the right atrium RA. The proximal flange 6308 is apposedto the septum 6302 on the right atrium RA side with all of its flangesegments extending radially outward. A distal end of all the proximalflange segments connects the proximal end of the core segment 6306, andthe proximal ends of the all proximal flange segments connect the hub6310. The hub 6310 connects to the proximal end of the proximal flange6308. The hub 6310 allows the device 6300 to be connected to a deliverysystem. As illustrated in FIG. 63, the device 6300 is securely situatedacross the aperture 6312 on the atrial septum 6302.

In some embodiments, the distal and proximal flanges may be attached oradjacent to the respective ends of the core segment and extend radiallyoutward from the longitudinal axis of the core segment. The distal andproximal flanges may be integral with the core segment and need not be“attached” thereto but may be fabricated from the same material thatdefines the core segment (including in the manners described herein) andthus may be contiguous therewith.

In some embodiments, one or more segments of either or both of thedistal and proximal flanges may be in the shape of a petal or a loop.Other design, shape, size, and configurations of flange segments arealso encompassed by the present invention. A flange may be in the shapeof an annular ring in which a continuous loop or a helical curve expandsradially outward when deployed. Each flange segment may be formed ofmultiple individual struts or may be formed of a single strut. The shapeand configurations of a distal or proximal flange may be the same as ordifferent from that of the other flange.

Referring now to FIG. 2, an embodiment of the interatrial pressure ventis illustrated. This embodiment of an interatrial pressure vent 100includes body element 101 comprising a substantially open mesh andincluding a substantially cylindrical core segment (shown end on) 106and substantially annular flanges 102 and 103. Flanges 102 and 103 maybe comprised of any number of flange segments (or “flange elements” or“flange members”) 102 a-102 h and 103 a-103 h, that are attachedadjacent to the end of the core segment and extend radially outward fromlongitudinal axis of the core segment and flow control element 104.“Flange segments” may also be referred to as “legs” herein. The flanges102 and 103 (and thus the segments which comprise them 102 a-h and 103a-h) in this and all embodiments disclosed herein, may also be integralwith the core segment. That is, they need not be necessarily “attached”thereto but may be fabricated from the same material that defines thecore segment (including in the manners described above and herein) andthus may be contiguous therewith. The flow control element may beattached to the body element, for example at locations 105. The flangesegments in this and any embodiment of any annular flange may be formedof two individual strut elements or also can be formed of a singleelement. The flange segments may be generally rectangular in crosssection, circular in cross section, oval in cross section or some othergeometric shape.

FIG. 64 shows an embodiment of the device 6400 is in a elongated,low-profile delivery configuration. This configuration is sometimesreferred to herein as a “delivery profile” and the configuration thatthe device has when it is deployed from the delivery system is sometimesreferred to herein as the “deployed profile”. It should be understoodthat a device may have its delivery profile configuration when it isbeing stretched on both ends or when it is constrained within a deliverycatheter. Both the distal and proximal flanges align with the coresegment along the longitudinal axis of the device. In some embodiments,the core segment may also be stretched longitudinally to a smalleroverall diameter in the delivery profile. In some other embodiments, theoverall size of the core segment remains unchanged from the deliveryprofile to the deployed profile.

Still referring to FIG. 64, an embodiment of the device 6400 is shown inits delivery profile where its proximal flange 6402, distal flange 6404,and core segment 6406 are aligned with each other to form a generaltubular shape 6408. The distal portion 6410 of the tube 6408 forms thedistal flange 6404 of the device 6400 upon deployment, and the proximalportion 6412 of the tube 6408 forms the proximal flange 6402 of thedevice 6400 upon deployment. The proximal portion 6412 of the tube 6408is configured to connect to a hub (not shown). Several slits, e.g.,first and second slits 6414, 6416, extend along the tube 6408 from onespot to another spot. The slits which are next to one another and areparallel to each other on tube surface and are offset longitudinallyfrom each other. The first slit 6414 extends from a first location to asecond location on the distal portion 6410 of the tube. The second slit6416 extends from a third location, proximal to the first location, tothe proximal end 6418 of the tube 6408. The second slit 6414longitudinally aligns with the first slit 6414 parallel to thelongitudinal axis of the tube. A third slit 6420 extends from a fourthlocation to a fifth location on the tube 6408. The third slit 6420 isparallel to the first and second slits 6414, 6416, and is radially nextto the first and the second slits 6414, 6416. The fifth location on thetube is proximal to the second location. A fourth slit 6422 extends froma sixth location, distal to the fifth location, to the distal end 6424of the tube 6408. The fourth slit 6420 longitudinally aligns with thethird slit 6418 and they both are parallel to the longitudinal axis ofthe tube 6408. The tube 6408 also has additional sets of slits, e.g.fifth and sixth slits 6426, 6428, that are similarly situated andaligned as are first and second slits 6414, 6416 but which arecircumferentially transposed along the surface of the tube 6408 as wellas additional sets of slits, e.g. seventh and eighth slits 6430, 6432,that are similarly situated and aligned as are third and fourth slits6420, 6422 but which are circumferentially transposed along the surfaceof the tube 6408.

As shown in FIG. 64, a strut, e.g., strut 6434, is formed between twoslits radially next to each other, e.g. second and sixth slits 6416,6428. The struts may bow or bend outward during the deployment so as toform the distal and proximal flanges 6404, 6402. Struts may have crosssections in the shape of a rectangle, circle, oval, or some othergeometric shapes. As shown in FIG. 64, a first junction 6436 is formedbetween the first, second, third, and seventh slits 6414, 6416, 6420,6430, and a second junction 6438 is formed between the first, third,fourth, and fifth slits 6414, 6420, 6422, 6426. The first junction 6436is part of the proximal flange 6402 of the device 6400 and the secondjunction 6438 part of the core segment 6406 of the device 6400. The tube6408 has additional sets of junctions, e.g. third and fourth junctions6440, 6442, which are similar to the first and second junctions 6436,6438 but which are circumferentially transposed along the surface of thetube 6408 from the first and second junctions 6436, 6438. Those skilledin the art will understand that the slit pattern and locations describedabove will vary with respect to the desired deployed shape of thedevice.

FIGS. 65-67 schematically illustrate partially-deployed devicesaccording to embodiments of the present invention. Referring to FIG. 65,which shows an embodiment in the deployed shape. The distal portion 6502of the device 6500 expands radially to form the distal flange 6504 whilethe proximal end 6506 of the device 6500 is still confined to its tubeshape. In embodiments, proximal end 6506 is trimmed to shorten it to alength desired for a device to be implanted. The segments of the distalflange 6504, which has flange segments one such flange segment shown as6508, are formed from struts between slits of the distal portion 6502 ofthe device 6500. One end of each distal flange segment originates fromthe core segment of the device 6500, while the other end originates fromthe distal end of the tube. In some embodiments, the distal flangesegments device 6500 upon deployment form a generally planar distalflange 6602 that is parallel to the septum (not shown).

Referring to FIG. 66, there is shown a schematic side-view of apartially-deployed device 6600. The distal flange segments of device6600 upon deployment form an distal flange 6602 with the distal flangesegments curved from the core segment toward the septum. As illustratedin FIG. 67 which shows a portion of device 6700 as it is being deployedin use, each distal flange segment 6702 of the device 6700 may have afirst curved section 6704 extending into the left atrium so as to form aspace between itself and the septal wall 6706 and a second curvedsection 6708 extending from the first curved section 6704 toward theseptal wall 6708. The distal flanges can have other shapes and forms.

FIG. 68 illustrates a fully deployed device 6800 without a hub accordingto one embodiment of the present invention. Upon the distal portion ofthe tube being released from the delivery device, the distal portion ofthe tube expands radially, shortening its axis distance. The strutsformed between slits at the proximal portion of the tube bend outwardforming the segments of the distal flange 6802. The proximal portion ofthe tube behaves similarly and forms the proximal flange 6804. Theproximal ends of the proximal flange segments form a tubular proximalend 6806 of the device, which is configured to connect to a hub (notshown). One end of each of the segments of proximal flange 6804originates at the proximal end of the core segment 6808, while the otherend originates at the proximal end of the device 6800.

In the embodiment illustrated in FIG. 63, upon deployment, the segmentsproximal flange 6308 each have a first curved section extending into theright atrium which forms a space between the segment and the septum6302, and a second curved section extending from the first curvedsection toward the septum 6302. The proximal flange may have othershapes and forms and the specific disclosures in the present inventionshould not be viewed as limiting.

Referring again to FIG. 68, the core segment 6808 is between the distaland proximal flanges 6802, 6804. The core segment 6808 is formed by aportion of the tube between the distal and proximal portions of the tubeexpanding radially and shortening longitudinally. The diameter of thecore segment 6808 may remain the same or it may expand, e.g., by afactor up to 3. Referring to FIG. 81, the second junction 8138 is on thecore segment 6808 of FIG. 68 and correlates to junction 6810 in FIG. 68.The core segment 6808 has a general tubular profile with a centralpassageway extending therethrough. The cross section of a core segmentand its central passageway may be circular, oval or polygonal, such assquare or hexagonal, or any other suitable shape as will be apparent tothose skilled in the art. Typically, the cross section of a core segmenthas a diameter generally ranging from 5 mm to 30 mm, and thecross-sectional area of the central passageway ranges from 19 mm² to 700mm².

Returning to embodiments of the implantable device, the distal flangesand proximal flanges may define a gap into which the septum fits. Such agap, the gap G is indicated in FIG. 68 between the distal and proximalflanges 6802, 6804 of device 6800. Such gaps may be smaller than thethickness of the septum in some embodiments. In such embodiments, as thedevice is being deployed across the septum, the proximal and distalflanges may flex to accommodate the septal tissue and the gap may expandwhen tissues is positioned therein. The gap may be zero in someembodiments. The gap may be negative in some embodiments. In suchembodiments, the flange segments on each side of the core segment crossone another in a relaxed radially expanded form so that when the deviceis implanted, they exert a pressure against the septum. The gap may belarger than the thickness of the septum to avoid abrasion to the septaltissue. The above description of the characteristics of gap G may applyto any of the embodiments disclosed herein.

In some embodiments, the most radially outward end of the at least oneor both of the distal and proximal flanges of the device may be foldedtoward the core segment longitudinally, so that the distance betweenmost outward tips of the distal and proximal flanges is shorter than thedistance between the ends of the distal and proximal flanges where theyconnect the core segment in the deployed configuration. In someembodiments, the most outward tips of the distal and proximal flangespress the septum and thereby secure the device in place.

The proximal flange segments may be oriented so they are not directlyopposed to the distal flange segments on the opposite side of the coresegment. This may be referred to as “radially off-set” or “angularlyoff-set” flanges or flange segments. This design eliminates pinchingpoints on the septum and reduces the chance for tissue injury. Thedistal flange segments may be arranged midway between two adjacentproximal flange segments.

The length of distal flange segments may be similar to the length ofproximal flange segments. The lengths of distal flange segments may beidentical to the lengths of proximal flange segments; the length ofdistal flange segments may be longer than the length of proximal flangesegments; or the length of distal flange segments may be shorter thanthe proximal flange segments.

According to some embodiments, each of the distal and proximal flangesincludes at least two flange segments. In particular embodiments, thedistal flange includes eight loops. Devices having between four and tenflanges may be formed. Devices according to the present invention mayinclude any number of flange segments. The most desirable number offlange segments on each distal and proximal flange depends on a varietyof anatomical and manufacturing factors. In some embodiments, the distaland proximal flanges have the same number of flange segments. In someother embodiments, the distal and proximal flanges have differentnumbers of flange segments.

The most outward ends of the distal flange and/or proximal flange may bedesigned to have a large area of contact with the septal wall in orderto minimize the stress concentration against the septal wall. The endsof distal and proximal flange segments may be rounded at their radiallyoutward ends to reduce stress concentrations against the atrial septumafter placement. This rounded shape can easily be formed as part of theintegral shape of the flange segment. While rounded shapes at the endsof the flange segments reduce stress on the septum, one skilled in theart should also understand that other variations are also contemplated

The thickness of a flange segment near its radially outer end may bedecreased to achieve less stress against the septal wall. A differentmaterial of higher flexibility could be used for the end portions of theflange segments. Varying the thickness of components of implantabledevices or selecting different materials to achieve desiredflexibility/stiffness properties is discussed multiple times herein andeach method applies to any and all embodiments of implantable devicesdiscussed herein.

The distal and/or proximal flange segments may be designed to be moreflexible than the core segment. In such embodiments, the increasedflexibility may be achieved in several ways. The struts forming thedistal and proximal flange segments may be smaller than the strutsforming the core segment such that an increased flexibility of theflanges in relation to the core segment or other flange members can beachieved. Flange segments may be made from a different material from thecore segment, for example, the flange segments may be made of materialwith a greater flexibility than that of the core segment material. Theflange segments may have a greater flexibility than the core segment (orthe remaining portion of the flange segment or the flange itself as thecase may be). This can reduce the probability of causing damage to thetissue of the septum while allowing the core segment to maintain astrong outward force against the septal opening and thus decrease theprobability that the device will become dislodged.

Referring to FIG. 68, the proximal flange 6804, distal flange 6802, andcore segment 6808 of the device 6800 include a substantially opensurface area. In some embodiments, each opening 6812 has a size of 1 mm²to 5 mm². In some embodiments, the opening surface area is 50-95% ofentire surface of the device.

The implantable device may be fabricated by methods described hereinincluding laser-cutting or acid-etching a pattern into a preformed tube,then shape-setting to the intended deployed configuration. A devicehaving an open structure may be formed from a hollow tube that has beenslotted using, for example, a machining laser or water drill or othermethod, and then expanded to form the open structure. The device mayalso be formed of a woven, knitted, or braided tubular metallic fabricsmade out of metallic strands. The term “strand” used here can be wires,cords, fibers, yarns, filaments, cables, threads, or the like, and theseterms may be used interchangeably. The device having an open structuremay be formed from wire that is pre-bent into the desired shape and thenbonded together to connect elements either by welding them or adhesivelybonding them. They could be welded using a resistance welding techniqueor an arc welding technique, preferably while in an inert gasenvironment and with cooling control to control the grain structure inand around the weld site. The welded joints may be conditioned after thewelding procedure to reduce grain size and coining or upset forging maybe employed to optimize fatigue performance.

In some embodiments, the device comprises a sheet material that may havea constant through-thickness. In some embodiments, pre-selected areas ofthe sheet material have reduced through-thicknesses in relation to thethrough-thickness of sheet material in other areas of the implantabledevice. The areas of reduced through-thickness are selected based upon adesire to provide these areas with greater flexibility. In embodiments,the through-thickness of the device may vary in magnitude between a highvalue where greater stiffness is desired and a low value where greaterflexibility is desired, wherein the low value is in the range of between40 and 99 percent of the high value.

FIG. 69 illustrates this feature of the invention. The device 6900 shownin FIG. 69 has some areas, such as first and second areas 6902, 6904, atwhich greater flexibility is desirable and some areas, such as third andfourth areas 6906, 6908 at which greater stiffness is desirable.Accordingly, the present invention contemplates providing one or more ofthe first and second, with thinner through-thicknesses in relation tothat of one or more of the third and fourth areas 6906, 6908. In someembodiments of the present invention, the through-thickness of one ormore of the first and second areas 6902, 6904 is in the range of between40 and 99 percent of the maximum through-thickness in one or more of thethird and fourth areas 6906, 6908.

The present invention contemplates that through-thickness may be locallyreduced in selected areas by way of any conventional means, e.g.,grinding, turning, etching, electrochemical machining. In some methodembodiments, a device having reduced through-sections in preselectedareas is made by a process in which a tube of a particular wallthickness is machined in preselected areas to locally reduce thethrough-thickness of the tube, and then a pre-selected pattern is cutinto the machined tube, e.g., by laser cutting, electrodischargemachining, or etching, to form a patterned tube which is thenthermomechanically formed into the shape the device is to have in useafter implantation. In some instances of this method, the reducedthrough-thickness areas have magnitudes which are in the range ofbetween 40% and 99% of the magnitudes of the maximum through-thicknessarea of the device.

As described in connection with FIGS. 2A and 2B, varying the width of astrut or segment or the diameter of a strut or segment can allow forvariations in flexibility. Such methods of varying the through-thicknessmay be implemented along with those described above to achieve a varyingflexibility profile for any embodiment disclosed herein, including thevarying flexibility profile mentioned above.

In some embodiments, the device is fabricated from a tube and thenshaped to its final configuration. If a sufficiently elastic andresilient material or a shape memory material such as nitinol, is used,the device can be preformed into the finished shape, i.e., deployedprofile, and then stowed during delivery in delivery profile and thedeployed profile will be regained after deployment. In some embodiments,the core segment and/or one or both of the distal and proximal flangesmay be manually expanded to the desired diameter and/or curved to apre-set shape, heat set in an oven while constrained to the desiredshape to memorize the desired device shape. The surface of the finishedassembly should be carefully prepared to insure is passivated and freeof surface imperfections that could be nidus for thrombus formation.

The device may be made of a biocompatible metal or polymer. In someembodiments, the device in whole or in part is made of a elasticmaterial, super-elastic material, or shape-memory alloy which allowsselected portions to distort into a generally straightened profileduring the delivery process and resume and maintain its deployed profilein vivo once it is deployed from the delivery catheter. Some of thematerials device may be made of in whole or in part include stainlesssteel, nitinol, Titanium, Elgiloy, Vitalium, Mobilium, Ticonium,Platinore, Stellite, Tantalum, Platium, Hastelloy, CoCrNi alloys (e.g.,trade name Phynox), MP35N, or CoCrMo alloys or other metallic alloys,and polymers such as PTFE, UHMPE, HDPE, polypropylene, polysulfone, orother biocompatible polymers. Part or all of the device may befabricated from a resorbable polymer such as polyactic acid,polyglycolic acid, polycaprolactone, a combination of two or more ofthese or a variety of other resorbable polymers that are well known tothose skilled in the art. The surface of the device may be textured toinduce tissue response and tissue in-growth for improved stabilization.

The device (open or monolithic) may comprise porous materials toencourage tissue ingrowth or to act as a reservoir for containing one ormore compounds that will be released over time after implant to addressnumerous issues associated with the product performance. These compoundsmay be used to diminish calcification, protein deposition, thrombusformation, or a combination of some or all of these conditions. Thecompound may be used to stimulate an irritation response to inducetissue ingrowth. The compound may be an anti-inflammatory agent todiscourage tissue proliferation adjacent to the device. The materialthat is used to make the device may be multilayered and comprise acoating of resorbable polymer or semipermeable polymer that may comprisevarious compounds that may be released, and in some embodiments in acontrolled manner over time, after implant to address numerous issuesassociated with product performance.

In embodiments, the distal flange, proximal flange, and core segment mayinclude integral marker holes or slots in which at least one radioopaquemarkers can be positioned so the device may more easily be visualizedusing radiographic imaging equipment such as with x-ray, magneticresonance, ultrasound, or fluoroscopic techniques. Radiopaque markersmay be swaged, riveted, or otherwise placed and secured in the hole andthereby dimensioned to be flush with the end of the material surroundingthe hole.

A device may have a hub which is configured to join the proximal ends ofthe proximal flanges segments. A hub may provide releasable attachmentpoint between the device and a delivery system.

A hub may include a hub body and hub cap. The hub body may be configuredto connect to the proximal end portions of the proximal flange segments.The hub cap may be configured to be fasten to the hub body so that theproximal end portions of the proximal flanges segments are securedinside the hub.

Each proximal end portion of each proximal flange segments may join to ahub. The proximal end portions of the proximal flange segments may bejoined with one another to form two proximal end joints with one or bothof the proximal end joints being joined to the hub. The proximal endportion of proximal flange segments may be joined to form more thanthree proximal end joints with one or more of the proximal end jointsbeing joined to the hub.

The hub body and the hub cap are attached together by a variety ofmeans. For example, the hub cap and hub body may be joined together bymechanical means such as by an interference connection between theinside of the hub cap and the outside of the hub body, by threadedconnection where the hub cap and the hub body have complementarythreads, or by crimping. The hub cap and hub body may be joined byenergy means such as heat, ultrasonic, or other types of welding etc.The hub cap and hub body may be joined by chemical means such asadhesive etc. Other means of the attachment known to those skilled inthe art can also be incorporated.

The hub cap may have cup shape comprising a tubular body with an openend and a closed end. The closed end of the hub cap may have an orificethat accommodates the delivery catheter-hub connection. The hub cap mayhave a sleeve shape. Although the term “tubular” has been used todescribe the exemplary configuration of the hub body and hub cap, it isto be understood that the cross section of the hub cap and hub body maybe circular, oval or polygonal, such as rectangular, square, orhexagonal. Other shapes and configurations can be used for the hub bodyand hub cap without departing the design principle disclosed herein.

The present invention includes embodiments in which the hub is connectedto a delivery catheter. As is illustrated in FIGS. 70A-B and 71A-B, thehub may be threadably connected to a delivery catheter. FIG. 70B shows across-sectional view taken along parting line 70B-70B of the hub 7002and the delivery catheter 7004. The hub 7002 includes a female thread7006 which is configured to connect to the male thread 7008 which islocated at the distal end of the delivery catheter 7004. FIG. 71Aillustrates the hub 7102 having male threads 7104 which are configuredto connect to the female threads 7106 located at the distal end of thedelivery catheter 7108. FIG. 71B shows a cross-sectional view takenalong parting line 71B-71B of the hub 7102 and the delivery catheter7108.

FIGS. 72A-B illustrates a hub 7202 having a groove 7204 which isconfigured to cooperate with a collet system 9806 at the distal end ofthe delivery catheter 7208. FIG. 72B shows a cross-sectional view takenalong parting line 72B-72B of the hub 7202 and the delivery catheter7208.

FIGS. 73A-B illustrate a ball-and-claw connection between a hub 7302 anda delivery catheter 7304 in which the hub 7302 includes a ball 7306configured to be secured by claws 7308 at the distal end of the deliverycatheter 7310. FIG. 73B shows a cross-sectional view taken along partingline 73B-73B of the hub 7302 and the delivery catheter 7304.

FIGS. 74A-B illustrate a pin-through-hole connection between a hub 7402and a delivery catheter 7404 in which the hub 7402 has an aperture 7406which is configured to receive fingers and/or pins, e.g., pins 7408, atthe distal end of the delivery catheter 7404. FIG. 74B shows across-sectional view taken along parting line 74B-74B of the hub 7402and the delivery catheter 7404.

75A-C illustrate an interlocking connection between a hub 7502 and adelivery catheter 7504 in which each of the hub 7502 and the distal endof the delivery catheter 7504 has a C-shaped element, i.e., hub C-shapedelement 7506 and delivery catheter C-shaped element 7508, wherein theC-shaped elements 7506, 7508 are configured to interconnect with eachother. FIG. 75A shows the hub 7502 and the delivery catheter 7504 priorto interconnecting. FIG. 75B shows the hub 7502 and the deliverycatheter 7504 after their respective C-shaped elements 7506, 7508 haveinterconnected. FIG. 75C shows a cross-sectional view along the verticalmid-planes of the hub 7502 and delivery catheter 7504 shown in FIG. 75B.

It is to be understood that connection mechanisms other than thosedescribed above may be used for connecting the hub and the deliverycatheter in accordance with the present invention.

In some embodiments, the end of the various embodiments of theimplantable device that is connected to or otherwise in engagement withthe delivery catheter is configured to allow some degree of freedom tothe device when such end is connected to or otherwise engaged with thedelivery catheter. For example, as the delivery catheter enters theright atrium, the delivery catheter may extend toward the atrial septumat a non-zero angle of up to 180 degrees “θ”. Embodiments allow theportion of the device that is primarily engaged with the septum to befree from distortion imposed by the delivery catheter. Such embodimentspermit the device to conform to the natural anatomy of the atrial septumas much as possible while still giving the clinician the ability ofretrieving the device if necessary due to the fact that the device canbe engaged with or otherwise connected to the delivery catheter as longas possible while deployed in the septum, but also while maintaining adelivery catheter angle that would compromise the delivery or otherprior art devices. FIGS. 76 and 77 illustrate two such embodiments.

FIG. 76 illustrates a mid-plane cross-sectional view of the proximal end7600 of a device described herein. The proximal end 7600 hereindescribed can be made part of the implantable devices described hereinsuch as those discussed in connection with FIGS. 22, 23, 46A, 46B, 63,65, 68, 69, and 83A. According to an embodiment in which each of theproximal portions, e.g. section 7602, of the proximal flange segmentshas a flexible section or pivotable section e.g, pivotable section 7604(as indicated by the bracket) optionally connected to a hub 7606. Theflexible section 7604 may allow the device 7600 to curve, turn, bend, ortwist as the proximal and distal flanges of the device 7600 are deployedacross and conform to the atrial septum. Such deployment may take placewhile the device 7600 is still connected to, or otherwise in engagementwith, the delivery catheter and the end of the delivery catheter (andconsequently the end of the device that is in engagement with thedelivery catheter) is angled away from the longitudinal axis of the restof the device. Such embodiments allow for a clinician to determine,while the proximal end of the device and the catheter delivery mechanismmaintain a non-zero angle up to 180 degrees with respect to thelongitudinal axis of the core segment of the device, whether deploymentof the portions of the device is satisfactory prior to releasing thedevice from engagement with the delivery mechanism.

The flexible section 7604 may also permit rotational displacement of thesection 7604 about the longitudinal axis of the core segment, forexample, allowing a clockwise or counter-clockwise displacement relativeto the proximal end of the proximal flange. Thus, the flexible section7604 may accommodate twisting relative to the remainder of the devicewhile allowing the remainder of the device to be satisfactorilydeployed.

In embodiments of the device having the general structure of thosedescribed herein the device may be configured to have a distal flangeadapted to be in contact with the left atrial side of the atrial septum;a core segment adapted to be in contact with the opening in the atrialseptum; a proximal flange having a portion adapted to be in contact withthe right atrial side of the atrial septum; and a pivotable endmentioned above. The pivotable or flexible end is connected to aproximal end of the proximal flange. Such connection may be integral. Asmentioned above, the pivotable end may adapted to be in releasableengagement with the delivery system while maintaining a non-zero angleup to 180 degrees with respect to the longitudinal axis of the coresegment of the device or a rotational displacement angle relative to theremainder of the deployed device, said displacement being about thelongitudinal axis. As mentioned above, the clinician may determine ifthe device is satisfactorily deployed prior to release. In embodiments,satisfactory deployment may mean that a portion of the distal flange isadapted to maintain contact with the left atrial side of the atrialseptum and a portion of the core segment is adapted to be in contactwith the opening in the atrial septum upon pivoting of the pivotableend. It may also mean that a portion of the proximal flange is adaptedto maintain contact with the right atrial side of the atrial septum uponpivoting of the pivotable end. Satisfactory deployment may also occurupon measurement of a physiological parameter prior to releasing thedevice from the deliver system. Such measurement may include themeasurement of the blood flow through the core segment, or the pressurein left atrium, the pressure in the right atrium, or both.

In embodiments, to achieve the flexibility/pivotability discussedherein, the end 7600 comprises a plurality of parallel struts whereineach of the struts within the longitudinal length of the flexiblesection has a plurality of alternating radially concave inward andradially concave outward curves. For example, referring to FIG. 76,curvy section 7604 includes first and second struts 7608, 7610, each ofwhich has a radially concave inward section A, a radially concaveoutward section B, a radially concave inward section C, and a radiallyconcave outward section D.

Another embodiment which gives the device freedom of movement at itsproximal end is shown in FIG. 77. FIG. 77 schematically illustrates theproximal end 7700 of a device. This proximal end 7700 comprises a hub7702 which has two posts 7704 a, 7704 b extending radially outward fromthe longitudinal axis of the device. Two sets of flexible flangesections 7706 a, 7706 b, each of which forms a collar at their junction,is rotatably attached to the posts 7704 a, 7704 b and held in place byendcaps 7708 a, 7708 b. This configuration permits the main portion ofthe device to rotate out of alignment with a delivery catheter to whichthe hub 7702 is attached.

FIGS. 78A-F schematically illustrate an embodiment of a device 7800which is being delivered to and deployed at a treatment site in theatrial septum 7802 of a patient's heart 7804. In FIG. 78A the device7800 is not visible as it is in its delivery profile and containedwithin the distal end portion of a delivery system 7806, which includesa delivery catheter and a sheath. The device 7800 is secured to thedelivery system 7806 so that the device 7800 can be placed accurately atthe desired delivery location, e.g., the treatment site 7802. Althoughhidden from view, the hub of the device is attached to the distal end ofthe delivery system 7806. The attachment mechanism also is configured toprovide a controlled deployment of the device 7800 so that the positionof the device 7800 as it is being deployed can be monitored. The device7800 may be withdrawn into the delivery system 7806 or repositioneduntil the final stage of the deployment process. Under somecircumstances, the device 7800 also may be retrieved after deploymenthas been completed. The manner in which the device 7800 is secured tothe delivery system 7806 and the process for deployment and/or retrievalof the device are described in detail below.

The delivery catheter of the delivery system 7806 is slidably disposedwithin the longitudinal passageway of the delivery sheath. The distalend of the delivery catheter releasably attaches to the hub of thedevice 7800. The device 7800 in its elongated delivery profile isconstrained within the distal end portion of the delivery sheath. Thedelivery sheath containing the device 7800 is first inserted into theright atrium RA of the patient's heart 7804. The distal end of thedelivery system 7806, including the delivery sheath may then be passedthrough an aperture 7808 which is located in the atrial septum 7802 andinto the left atrium LA of the patient's heart 7804. The distal portionof the device 7800 may then be exposed into the left atrium LA by movingthe delivery sheath proximally while holding delivery catheter steady orby advancing the delivery catheter distally while maintaining deliverysheath in place or by moving the delivery sheath proximally whiledistally advancing the delivery catheter. (Note that general methods ofdelivery are described herein and others are known to the skilledartisan). As it becomes exposed, the distal portion 7810 of the device7800 begins to expand into the left atrium LA—see FIG. 78B.

The delivery sheath holding the proximal portion of the device 7800 andthe delivery catheter attached to the device 7800 may then be pulledback through the aperture 7808 and into the right atrium RA so that thecore segment 7812 of the device 7800 is positioned within the aperture7808 and the distal flange 7814 of the device 7800 seats against theleft atrium LA side of the atrial septum 7802, as shown in FIG. 78C.

Referring now to FIG. 78D, the proximal portion of the device 7800 isthen exposed into the right atrium RA by withdrawing the delivery sheathfurther proximally while holding delivery catheter steady or byadvancing the delivery catheter distally, while maintaining deliverysheath in place or by moving the delivery sheath proximally and distallyadvancing the delivery catheter. When properly deployed, the coresegment 7812 of the device 7800 is disposed within or through theaperture 7808 with the device's 7800 distal flange 7814 on the leftatrium LA side of the atrial septum 7802 and the device's 7800 proximalflange 7816 on the right atrial side of the atrial septum 7802. Thedistal flange 7814 and proximal flange 7816 may exert a compressiveforce against the atrial septum 7802 securing the core segment acrossthe aperture 7808. The positioning of the device 7800 can be evaluatedusing fluoroscopy or other appropriate techniques.

FIG. 78E shows the device still connected to or engaged with thedelivery system 7608. As can be seen the angle of approach (θ of FIG.79) of the delivery system 7608 is non-zero with respect to thelongitudinal axis of the core segment 7812 of the device. As discussedabove, the pivotable end of the device allows for the device 7800 tomaintain its connection to, or engagement with, the delivery systemwhile (a) the significant operable features of the device are deployedin the septum, and (b) accommodating the angle mentioned above. In thisway, the clinician can determine if the device 7800 is satisfactorilydeployed and/or if the physiology of the patient is such that the device7800 may be released from engagement with the delivery system. Beforedisengaging, if deployment is incorrect or questionable, or if themeasured physiological parameters of the patient reveals a problem, thedevice may be retrieved by retracting the device back into the deliverysystem as discussed below.

When the clinician who is implanting the device is satisfied with thedevice's location and deployment characteristics and/or physiology ofthe patient upon deployment, the attachment between the hub of thedevice and the distal end of the catheter is then detached to releasethe device 7800 from the delivery system 7806 and the delivery system7806 pulled distally away from the device 7800, as illustrated in FIG.78E. The device 7800 remains implanted in the aperture 7808 of theatrial septum 7802. The delivery system is then removed from the heart.However, in some cases, if the clinician is not satisfied with thelocation of the device 7800, the delivery system 7806 may be used toretrieve the device 7800.

To retrieve the proximal portion of a device back into the deliverysystem before the hub of the device has been detached from the deliverycatheter, the delivery sheath may be advanced distally while thedelivery catheter is pulled proximally or the delivery sheath may beadvanced distally while the delivery catheter is held steady or thedelivery catheter may be pulled proximally while the delivery sheath isheld steady. Any of these actions will cause the proximal flange toenter into the distal end of the delivery sheath and resume itselongated delivery profile within the delivery sheath. To retrieve thedistal portion of the device back into the delivery system, the deliverysheath may be advanced distally while the delivery catheter is pulledproximally or the delivery sheath may be advanced distally while thedelivery catheter is held steady or the delivery catheter may be pulledproximally while the delivery sheath is held steady. After the device isfully withdrawn into the delivery system, the delivery system may beremoved from the body or the device can be redeployed according to stepsof the delivery sequence described above.

In embodiments, the flange segments are designed to be more flexiblethan the core segment. In such embodiments, the increased flexibilitymay be achieved in several ways. In embodiments, a dimension of thesurface of the strut elements that make up the flange segments isaltered relative to the corresponding dimension of the struts (orelements, or members) that make up the core segments. FIG. 2Aillustrates such embodiments. FIG. 2A shows an example flange segment103 a viewed end on. As shown, the end-facing dimension of strut elementof 103 x has a width D. By decreasing the width D in relation to thewidth of the outward-facing dimension of the struts that comprise thecore segment, an increased flexibility of the flanges in relation to thecore segment or other flange members (or portions thereof) can beachieved. FIG. 2B shows an enlarged fragmentary cross-section of anembodiment of the device substantially shown in FIG. 6. The view istaken along line 7-7 of FIG. 6. In this figure, the cross hatched areashows the area of increased flexibility. It can be seen that one area ofthe flange segment is thus more flexible than another area. Inembodiments where the strut elements are circular, then in a similarfashion, the diameter of the strut element could be made to have adiameters less than the diameter of the strut (or similar elements)comprising the mesh-like configuration of the core segment.

In embodiments where the flange element is made from a different sectionof material and is attached to the core segment, the segment materialcould be chosen to have a greater flexibility than the core segment (orremaining portion of the flange segment or flange itself as the case maybe). The choice of materials based on their flexibility will be apparentto those skilled in the art. In the ways described above, the flangesegments can achieve greater flexibility than the core segment (or theremaining portion of the flange segment or the flange itself as the casemay be) thereby reducing probability of damage to the tissue of theseptum while allowing the core segment to maintain a strong outwardforce against the septal opening and thus decrease the probability thatthe device could become dislodged.

In embodiments having an open-mesh configuration for the body element101, the body element can be formed from a number of materials suitablefor use in a patient, such as titanium, nitinol, stainless steel,Elgiloy®, MP35N®, Vitalium, Mobilium, Ticonium, Platinore, Stellite®,tantalum, platinum, or other resilient material. Alternatively, in suchembodiments, the body element 101 can be formed from a polymer such asPTFE, UHMWPE, HDPE, polypropylene, polysulfone, or other biocompatibleplastic. The surface finish of the body element may be smooth with noedges or sharp discontinuities. In other embodiments, the surface finishis textured to induce tissue response and tissue in growth for improvedstabilization. In embodiments, the open mesh of body element 101 can befabricated from a resorbable polymer such as polylactic acid,polyglycolic acid, polycaprolactone, a combination of two or more ofthese or a variety of other resorbable polymers that are well known tothose skilled in the art.

In embodiments, the structure of the body element may be uniform andmonolithic.

In other embodiments, the body element (mesh or monolithic) may compriseporous materials to encourage tissue ingrowth or to act as a reservoirfor containing one or more compounds that will be released over timeafter implant to address numerous issues associated with the productperformance. These compounds can be used to diminish calcification,protein deposition, thrombus formation, or a combination of some or allof these conditions. The compound can also be used to stimulate anirritation response to induce tissue ingrowth. In embodiments, thecompound can be an anti-inflammatory agent to discourage tissueproliferation adjacent to the device. Numerous agents are available forall of such uses and are familiar to those who are skilled in the art.

In embodiments, the material that may comprise the body may bemultilayered comprising a coating of resorbable polymer or semipermeablepolymer that may comprise various compounds that may be released, and insome embodiments in a controlled manner over time, after implant toaddress numerous issues associated with product performance.

The mesh can be formed from wire that is pre-bent into the desired shapeand then bonded together to connect the component elements either bywelding them or adhesively bonding them. They could be welded using aresistance welding technique or an arc welding technique, preferablywhile in an inert gas environment and with cooling control to controlthe grain structure in and around the weld site. These joints can beconditioned after the welding procedure to reduce grain size usingcoining or upset forging to optimize fatigue performance.

In other embodiments, the mesh can be formed from a hollow tube that hasbeen slotted using, for example, a machining laser or water drill orother method and then expanded to form the open structure. If asufficiently elastic and resilient material, such as nitinol, is used,the structure can be preformed into the finished shape and thenelastically deformed and stowed during delivery so the shape will beelastically recovered after deployment. The surface of the finishedassembly must be carefully prepared to insure is passivated and free ofsurface imperfections that could be a nidus for thrombus formation.

In embodiments, the flow control element 104 is a tissue valve such as atricuspid valve, a bicuspid valve or a single flap valve formed frompericardial tissue from a bovine, porcine, ovine or other animal. Anynumber of cusps may be used. The flow control element is formed using anumber of processing steps and auxiliary materials such as are wellknown in the art.

The flow control element 104 can also be a ball valve, a duckbill valve,a leaflet valve, a flap valve, a disc in cage type valve, a ball in cagetype valve or other type of valve formed from a polymer or polymers or acombination of polymers, ceramics and metals such as Dacron (polyester),PTFE (such as Teflon®), polyurethane, PET or other suitable polymer;titanium, stainless steel, nitinol, MP35N®, cobalt-chromium-nickel alloy(such as Elgiloy®), or other suitable metal; zirconia, silicone nitride,or other suitable ceramic. Valves or portions thereof may comprisedifferent stiffness/flexibly properties with respect to other valves orportions thereof in the flow control element.

The flow control element 104 preferably extends to a point along theflange assembly 103 to enable creation of a sealable connection to theseptum wall after placement. This is more particularly shown in FIG. 3where it can be seen that in embodiments, the flow control elementextends beyond the length of the core segment and is folded and attachedto the core segment so as to create a lip that extends in a directioncenter of the opening in the vent. When the device is abutted againstthe septal wall, this lip forms said sealable connection and thus canreduce the likelihood that blood can flow through the septal opening viapathways between the outer surface (septal-facing surface) of theinteratrial pressure venting device and the septal opening. The flowcontrol element 104 is attached to the body element 101. This can beaccomplished by using a suture material, such as silk, nylon,polypropylene, polyester, polybutylester or other materials such as arewell known to those skilled in the art. In embodiments, flow controlelement 104 can be attached to body element 101 using adhesive bondingagents such as cyanoacrylate, polymethylmethacrylate, or other materialssuch as are well known to those skilled in the art. In otherembodiments, flow control element 104 can be attached to body element101 via staples, rivets, rings, clamps or other similar methods as arewell known to those skilled in the art.

As mentioned above, flow control element can be made of materialselected for its flexibility/stiffness. In embodiments where a loosevalve is desired that resonates more closely with the cycle of theheart, a however stiffness material may be chosen. In embodiments whereit is desired to open the valve when the pressure differential reaches aselected value, the material of the flow control element can be selectedand/or processed in a manner to open at the desired differential. Theleaflets or sections of the flow control element itself may alsocomprise areas of variable stiffness, and or may be more flexible orless flexible than other leaflets or components of the flow controlelement.

FIG. 3 shows an embodiment of the device implanted in the atrial septumof the heart of a patient. As can be seen from the figure, the coresegment 106 can be formed contiguously with flanges 102 and 103 and thusflange segments 102 a-102 h and 103 a-103 h respectively. In theembodiment shown, flow control element 104 is contained within the coresegment 106 so it does not extend beyond the face of the body element101, thereby insulating it from contact from other body structures orperipheral tissue. In embodiments, the core segment 106 can be extendedto protrude beyond the interatrial septum 107 and the flange assembly102 and/or 103 on at least one side of the interatrial septum 107 andcan be formed with a shape that extends to create a lip in the mannerdescribed above. In embodiments, the ends of the flange assemblies 102,103 are formed to lie at a parallel angle to and against the septal wallalong at least a part of its length to increase the area of contact andthereby decrease the stress concentration against the septal wall.

Referring now to FIG. 4, an embodiment of the implantable device isshown. This perspective view implantable device 101 shows how, inembodiments, the ends of flange segments 102 a-102 h, 103 a-103 h arerounded at their distal ends 115 and 116 to reduce stress concentrationsagainst the interatrial septum after placement. This rounded shape caneasily be formed as part of the integral shape of the flange segment. Inother embodiments, the thickness of the segment in this area may bedecreased to decrease the stress further against the interatrial septum,which is similar to embodiments described above. Also similar toembodiments described above, if the segment is round, the diameter canbe decreased in order to increase flexibility. Also, as described abovea different material of higher flexibility could be used for the endportions of the segments.

While rounded shapes at the ends of the flange segments reduce stress onthe septum, other variations on this theme are contemplated. FIGS. 7Athrough 7C illustrate embodiments where the shape of the end portions ofthe flange segments has configurations to achieve less stress againstthe septal wall—among other goals. FIG. 7A is a side elevational view ofembodiment of the pressure venting device in its stowed configuration.Core segment 106 of body element 101 is shown and, in this embodiment,is integral with flanges 103 and 102. The individual flange segments arenot labeled; however, it is easily seen that flange 103 comprisessegments substantial similar to those described above. There is noeyelet or opening at the end of the segment in the embodiment shown.Flange 102 shows an embodiment where the flange segment is not comprisedof a triangular or multi-strut arrangement as described above but rathera single-member segment. Any flange may be constructed withsingle-member segment. An example single member is referred to as 103 s.In this example, at the end of each single-member flange segment (102 s)for example, there is an eyelet. FIG. 7B shows an embodiment similar tothat shown in FIG. 7A where the end of the segments 102 s are noteyelets but rather pads. FIG. 7C shows another embodiment where the endsof the segments 102 are paddle shaped. Other smooth-edged shapes couldbe used, and it should be understood that such shapes and configurationsapply to all manner of flange segment ends, not only single-membersegments. This would include the ends of flange segments shown anddescribed herein, for example with reference to FIGS. 2 through 7.

FIGS. 7A-C also show embodiments having at least one flange segmentbeing longer than the other flange segments. Again, while represented assingle-member flange segments they need not be and as such aconfiguration with at least one longer segment may apply to anyflange-segment configuration disclosed herein. The benefits and purposeof having at least one longer flange segment will be described morefully below.

In embodiments, the outer ends of the flange segments 102 a-102 h, 103a-103 h are formed with integral marker holes or slots 109 and 110(shown in FIGS. 3 and 7 for example) in which markers 118 and 119 can bepositioned so the device may more easily be visualized usingradiographic imaging equipment such as with x-ray, magnetic resonance,ultrasound or other imaging techniques. Markers as disclosed herein maybe applied to the ends of any segments, not just those with holes oreyelets therein. A radiopaque marker 118 and 119 can be swaged, riveted,or otherwise placed and secured in the hole and thereby dimensioned tobe flush with the end of the segment. Markers may also be simplyattached or to end of a segment not having a hole. In all embodimentshaving markers, flange ends 115 and 116 are more visible when imaged. Inother embodiments, the markers 118 and 119 can be bonded with anadhesive agent such as cyanoacrylate or epoxy or a variety of othermaterials that are available and suitable for implant as are well known.The markers may be proud (as shown for example in FIG. 7) or flush withthe end of the flange segment. The radiopaque markers 118 and 119 may beformed of tantalum, tungsten, platinum iridium, gold, alloys of thesematerials or other materials that are known to those skilled in the art.Also markers 118 and 119 comprising cobalt, fluorine or numerous otherparamagnetic materials or other echogenic materials that are known tothose skilled in the arts can be incorporated together with theradiopaque materials, or in alternating locations of the flange segmentsto enable both x-ray and echographic imaging of the interatrial pressurevent. Alternatively, the ends of the flange elements 102 a-102 h and 103a-103 h can be wrapped with a foil made of the same marker materials. Inembodiments, the radiopaque material can be laminated to the flangesegments and bonded through a welding process or using an adhesive suchas cyanoacrylate or numerous other adhesives known to those skilled inthe art.

Suture rings 117 can be formed in the body element to locate and fix theattachment site along the body element to the flow control element. Thesuture rings can be circular holes formed into the structure or theycould also be some other shape such as rectangular or triangular andalso can be formed as a secondary step, for example by standardmachining techniques, using a secondary laser machining step, or withelectrochemical etching. Preferably the connection between a segment andany other segment of the body element are formed with as large a radiusas possible to increase resistance to fatigue failure. Also, preferably,all edges of the formed device are rounded to improve biocompatibilityand hemocompatibility.

The pattern of suture rings as well as which of the rings are selectedduring suturing may affect the properties of the flow control element.For example, in embodiments where it is desired to have the flow elementloose and flappable, less suture rings may be utilized and, in suchembodiments, RA-side end of the flow control element may containrelatively less sutures than the LA side. In other embodiments, it maybe desirable to keep the flow control element affixed to the coresegment for a increased length of the segment thereby reducing theamount of flow control element material that affecting flow. Still inother embodiments the top or bottom portion the flow element at the RAside may be sutured in such a way so as to allow the top or bottomportion of the flow control element to affect flow more than the otherportion respectively. Embodiments discussed below where the flow is“aimed” may utilize suturing patterns effective to enable the desiredflow control element configuration.

Returning to the flange segments, in an embodiment, the interatrialpressure vent 100 is comprised of an equal number of flange segments oneach side of the interatrial septum. In embodiments, there are eightflange segments on each side of the core segment. In another aspectthere are an equal number of suture rings and flange segments on oneside of the interatrial pressure vent. In other embodiments, there areseven flange segments on each side of the core segment. In otherembodiments, there are six flange segments on each side of the coresegment. In other embodiments, there are five flange segments on eachside of the core segment. In other embodiments there are four flangesegments on each side of the core segment. In other embodiments thereare three flanges on each side of the core segment. In other embodimentsthere are two flanges on each side of the core segment. In otherembodiments, there is one flange on each side of the core segment. Stillin other embodiments there are more flange segments as compared toflange segments. And in other embodiments, there are more flangesegments as compared to flange segments. As can be seen there are anumber of variations for the number of flange segments and the skilledartisan will appreciate that any number could be used while notdeviating from the scope and spirit of this invention.

Referring now to FIG. 5, an embodiment of the implantable device isdisplayed in side view. The flange segments can be formed to produce agap G (also referred to as an annular gap) between the ends of flangesegments on one side of the body and flange segments on the other sideof the body, when the device is in its “native” or un-deployed state.When the device is deployed, it flexes to accommodate the tissue and assuch the gap may expand when tissue is positioned therein. Inembodiments, this gap is slightly smaller than the thickness of theinteratrial septum. In other embodiments, the gap can be larger than thethickness of the interatrial septum. In other embodiments the gap can bezero. In another aspect the gap can be negative: in this case the flangesegments on each side of the body can be formed to cross each other inorder to exert more pressure between the deployed flange segments andthe interatrial septum. Also shown in FIG. 5 are radiopaque markers 118and 119, which in embodiments are shown to be located adjacent to theend of the flange segments.

Referring now to the embodiment shown in FIG. 6, the flange segments 102a-102 h are oriented so they are not directly opposed to flange segments103 a-103 h on the opposite side of the body element so that afterplacement there is no pinching points thereby reducing the chance fortissue injury. In embodiments, flange segments 102 a-102 h are arrangedmidway between adjacent ends of flange segments 103 a-103 h. Inembodiments the length of flange segments 102 a-102 h are similar to thelength of flange segments 103 a-103 h. However, in other embodiments thelength of flange segments 102 a-102 h are identical to the length offlange segments 103 a-103 h; the length of flange segments 102 a-102 hare longer than 103 a-103 h; and the length of flange segments 102 a-102h are shorter than flange segments 103 a-103 h.

Referring now to FIG. 7, in embodiments having radiopaque markers it canbe seen that the radiopaque markers 118 and 119 may be placed into themarker holes 109 and 110 (or placed on the ends of flange segments thatdo not have holes) to locate the ends of the flange segments 102 a-102 hand 103 a-103 h with a non-invasive imaging technique such as with x-rayor echo sound during or after the procedure. In embodiments, the markers118 and 119 can be formed to be flush in an axial direction with theouter surface and the inner surface of the flange segments 102 a-102 hand 103 a-103 h. In another aspect, the markers 118 and 119 can beformed to extend in an axial direction beyond the outer surface of theflange segments 102 a-102 h and 103 a-103 h, away from the interatrialseptum. In embodiments, the markers 118 and 119 can be formed to extendin an axial direction beyond the inside of the flange segments 102 a-102h and 103 a-103 h, toward the interatrial septum. In embodiments, themarkers 118 and 119 can be formed to extend in an axial direction beyondthe inside and the outside of the flange segments 102 a-102 h and 103a-103 h. In embodiments, the markers 118 and 119 can be formed to berecessed in an axial direction within the surface of the inside of theflange segments 102 a-102 h and 103 a-103 h. In embodiments, the markers118 and 119 can be formed to be recessed in an axial direction withinthe outside of the flange segments 102 a-102 h and 103 a-103 h. Inembodiments, the markers 118 and 119 can be formed to be recessed in anaxial direction within both the inside and the outside of the flangesegments 102 a-102 h and 103 a-103 h. In embodiments, the markers 118and 119 can be formed to extend in a radial direction within the widthof the flange segments 102 a-102 h and 103 a-103 h. In embodiments, themarkers 118 and 119 can be formed to extend in a radial direction flushwith the width of the flange segments 102 a-102 h and 103 a-103 h.

Referring now to FIG. 8, an interatrial pressure vent 100 is shown inits stowed configuration. In embodiments, the interatrial pressure ventcan be collapsed to a substantially cylindrical shape for stowing in adelivery catheter during placement. Flange segments 102 a-102 h and 103a-103 h can be fabricated to be substantially equal in length. The“stowed position” is not meant to apply only to devices having flangesegments of equal length but rather to all embodiments of the ventingdevice disclosed herein. Devices having flange segments of varyinglength and orientation such as those described herein are also designedto stow in substantially the same manner as shown in FIG. 8. In anembodiment 200 seen in FIG. 20, flange segments 202 a-202 h and 203a-203 h are formed on a slanted angle so that, when marker elements aresecured to the ends of the flange segments, the flange segments can bestowed into a smaller volume. In embodiments 300 seen in FIG. 21, flangesegments 302 a-302 h are formed of alternating length to allow stowageinto a smaller volume.

Referring now to FIG. 9, an embodiment of the distal end of theplacement catheter 111 is shown in its open position. The inner shaft112 is fabricated with a center lumen 136 of sufficient diameter tocontain a guidewire 138 or also for use in injecting contrast or otherliquid. Commonly, the lumen would be sized for a guidewire of 0.010″,0.011″, 0.014″, 0.018″, 0.021″, 0.028″, 0.035″, 0.038″, 0.042″ or0.045″. This lumen 136 can also be used to measure pressure at thedistal end of the catheter using other equipment and techniques that arewell known to those skilled in the art. The lumen 136 preferably extendsthrough the entire length of the inner shaft 112. Alternatively, theguidewire lumen 136 can extend for a shorter length in the proximaldirection and then through a side hole (not shown) of the inner sheath.A corresponding side hole (not shown) is placed on the outer shaft 113adjacent to the side hole in the inner shaft 112 to create a pathwaybetween the center lumen 136 of the inner shaft 112 and the outside ofthe outer shaft 113. In this way it is possible to pass a guidewire fromthis distal end of the inner lumen 136 through the side hole andexchange the catheter over a guidewire that is less than twice thelength of the catheter 111 while securing the guidewire position duringexchange.

In embodiments, the inner shaft 112 is configured with a waist section120 to contain the folded interatrial pressure vent 100 between the gapformed in the space outside of this section of inner shaft 112 and theinside of the outer shaft 113. The inner shaft 112 may be formed tocontain at least one circumferential groove 114 at the proximal end ofwaist section 120 that forms a recess between the inside of the outershaft 113 and the smallest diameter of the groove that is greater thanthe gap formed in the space between the waist section 120 and the insideof the outer shaft 113. Radiopaque markers 118 can extend in a radialdirection past the outer surface of the flange segments 102 a-102 h andin embodiments, when interatrial pressure vents are folded into theirstowed configuration and placed into position over inner shaft 112,radiopaque markers 118 are dimensioned to fit into groove 114. Othersimilarly dimensioned sections may be used; that is, that which fitsinto the groove need not necessarily be a radiopaque marker. Inembodiments, when interatrial pressure vents are stowed in this manner,the gap between waist section 120 and the inside of outer shaft 113 isnot sufficient to allow radiopaque markers 118 beyond the distal end ofgroove 114 unless the outer sheath 113 is retracted beyond the proximalend of groove 114.

The inner shaft 112 may be formed with a groove 121 on the distal end ofthe waist section 120 adjacent to the location of the distal end of theinteratrial pressure vents are radiopaque markers 119 (or similardimensioned members) can extend in a radial direction past the outersurface of the flange segments 102 a-102 h and in embodiments, wheninteratrial pressure vents are folded into its stowed configuration andplaced into position over inner shaft 112, radiopaque markers 119 aredimensioned to fit into groove 121. In another aspect, the inner shaft112 may be formed with a circumferential groove 114 on the proximal endof waist section 120 and a circumferential groove 121 on the distal endof the waist section 120 The inner shaft can be formed of a variety ofpolymers or metals or combinations of polymers and metals that aresuitable for use in a patient. The inner shaft can be fabricated from asingle length of PTFE, UHMWPE, FEP, HDPE, LDPE, polypropylene, acetal,Delrin, nylon, Pebax, other thermoplastic rubber, aliphatic or aromaticpolyurethane, or a variety of other engineering resins that are wellknown to those skilled in the art. In embodiments, the inner shaft canbe fabricated using multiple layers of two or three of theabove-mentioned polymers to combine desirable properties of each. Forexample, the outer surface could be composed of polyurethane to enableeasier bonding of auxiliary components to the inner shaft. The innerlayer could be PTFE to convey better lubricity to the inner shaft. Inembodiments, the inner shaft and or the outer shaft could be coated onthe inner and or outer surface with a coating material that conveysspecific properties to the shaft like antithrombogenicity or lubricity.There are numerous available coating materials suitable for thesepurposes as are well known to those skilled in the art. The inner shaftcan be compounded with a radiopacifier to increase the visibility of theinner shaft under fluoroscopy using bismuth salts such as bismuthsubcarbonate, bismuth oxychloride, bismuth trioxide, tungsten powder,molybdenum powder or other radiopacifier such as are well known to thoseskilled in the arts. Similarly, the outer sheath can be fabricated fromthe same set of materials as the inner sheath, in the same manner andusing the same coatings. Embodiments described below in connection witha flange rather than circumferential groove operate in substantially thesame manner as described above and herein, except the device does notnecessarily have projections that fit into and are retained by thegrooves.

Referring now to FIG. 10, a folded representative interatrial pressurevent 100 is shown in its stowed position with the placement catheter 111shown in its open position. In practice, if the body of the interatrialpressure vent is fabricated of nitinol or other elastic material, whenthe placement catheter is in its fully open position, the flangesegments 102 a-102 h and 103 a-103 h would automatically recover into ashape like that shown in, for example, FIG. 4, hence this Figure isshown to illustrate the position of the interatrial pressure vent 100relative to the waist section 120 and grooves 114 and 121. Whenradiopaque markers (or similarly dimensioned members) 118 extend beyondthe thickness of the inside of body segment 101 of interatrial pressurevent 100, they form a projection within interatrial pressure vent 100that can be captured within groove 114 to secure the position of theinteratrial pressure vent 100 during placement. During deployment, theouter shaft 113 of placement catheter 111 is retracted a sufficientdistance to reveal the distal portion of the interatrial pressure vent100 allowing the flange segments 103 a-103 h to dilate radially awayfrom the central longitudinal axis of body 101. By capturing theradiopaque 118 markers within the groove 114, the device can berepositioned easily without further deployment, or the device can becompletely retracted and removed from the patient without deployment asindicated in FIG. 17.

Referring now to FIG. 11, an interatrial pressure vent 100 is showncompletely stowed within the placement catheter 111.

FIG. 11A shows an embodiment of the placement catheter similar inoperation to those described herein but operative to engage aninteratrial pressure vent by way of a slightly different mechanism thandescribed above in connection with circumferential grooves. This figureshows a schematic depiction of a stowed interatrial vent. Rather thanhaving the grooves as described above, this embodiment of a placementcatheter may comprise an inner shaft having a flange or member 3000(rather than a groove) which has a diameter larger than that of theinner shaft to grip and hold an end of the interatrial vent device asshown. As shown in the figure, the flange and its segments (collectivelyreferred to in the figure as 102) wrap around the ball-shaped flange3000 and allow the interatrial pressure vent to be moved with theplacement device in the manners described herein.

Referring now to FIG. 12, a placement catheter 111 is shown. It shouldbe noted that while the inner shaft is depicted as having grooves inFIG. 12, the inner shaft may comprise the flange 3000 as described abovein connection with FIG. 11A. The skilled artisan will appreciate thatthe operation of the device is substantially similar whether grooves orflanges are utilized. The placement catheter 111 may comprise a firsthandle component 128 that can be attached to outer shaft 113. The firsthandle component can be attached to the outer shaft 113 using a varietyof adhesive methods such as solvent bonding using a solvent for both thehandle and outer shaft material; an organosol consisting of a solventand polymer in solution that is compatible with both the outer shaft andthe first handle component; a polymerizable adhesive, such aspolyurethane, cyanocrylate, epoxy or a variety of other adhesives as arewell known to those skilled in the art. The first handle component canbe fabricated from a variety of metals such as aluminum, stainlesssteel, titanium or a number of other metals and alloys as are well knownto those skilled in the art. In embodiments, the first handle component128 is fabricated from a polymer such as polycarbonate, or a variety ofengineering resins, such as Lexan®, or others as are well known to thoseskilled in the art.

The first handle component may comprise hand grip section 124 andtubular shaft section 125. The tubular shaft section 125 can containkeyway 122 that is formed or machined into the shaft section. The keywayis preferably formed with three linear sections; a first linear section131, a second linear section 132 and a third linear section 133. Each ofthese sections is formed to traverse along a path primarily parallelwith the center axis along the length of the first handle component buteach is displaced radially from one another by at least about half ofthe width of the keyway. The placement catheter 111 also can comprise asecond handle component 129 that can be attached to inner sheath 112.The second handle component can be fabricated from the same variety ofmetals and polymers as the first handle component. The two handles canbe fabricated from the same materials or from different materials. Thesecond handle component can be attached to the inner sheath in the samemanner and using the same materials as the first handle componentattaches to the outer sheath. In embodiments, the second handlecomponent can contain threaded hole 126 for containing set screw 127.The set screw can be twisted to capture the inner shaft against thesecond handle component. The second handle component 129 also cancomprise a second hand grip section 134 and second tubular shaft section130. The second tubular shaft section can contain key 123 that is formedor machined of suitable dimension to adapt to keyway 122 of first handlecomponent 128. When assembled, second handle component 129 can beslideably moved relative to first handle component 128 in a mannercontrolled by the shape and length of the key way 122. As the secondhandle 129 is advanced relative to the first handle 128, it can beappreciated that the inner sheath 112 will slide in a distal directionout from the outer sheath 113. It can be appreciated that when thesecond handle component 129 is assembled, the key 123 is slid into thefirst linear section 131 and advanced until it hits the edge of thekeyway formed between the first linear section 131 and the second linearsection 132. In order for the second handle component 129 to advancefurther, it must be rotated and, once rotated, it can be advancedfurther but will stop when the key 123 hits the edge of the keywayformed between the second linear section 132 and the third linearsection 133. The keyway dimensions are preferably selected withconsideration for the combination of lengths of other components in theplacement device.

A first position, defined as the position when the key 123 is in contactwith the proximal edge formed between the first linear section 131 andthe second linear section 132, is preferably determined so, when fullyassembled and with the interatrial vent in its stowed position withinthe placement catheter, the outer shaft 113 will completely cover thelength of the interatrial pressure vent 100 as is desired duringcatheter placement. The keyway dimensions can also be selected to resultin a second position, defined as the position when the key 123 is incontact with the distal edge formed between the second linear section132 and third linear section 133. The second position would preferablybe selected to reveal the full length of flange segments 103 a-103 h butretain flange segments 102 a-102 h within the outer shaft 113 of thecatheter. The length of the third linear section 133 would preferably beselected so that, when the second handle component 129 was advancedcompletely against the first handle component 128, the full length ofthe interatrial vent 100 would be uncovered by the outer shaft 113 andthe device would be deployed. A variety of other configurations of thefirst and second handle components could be used for this same purpose.The first handle component tubular shaft section 125 and the secondhandle component tubular shaft section 130 could be threaded (not shown)so the first handle component 128 could be screwed into the secondhandle component 129. Alternatively, gear teeth (not shown) could beformed in the first tubular shaft section 125 of the first handlecomponent 128 and a gear wheel (not shown) could be incorporated intothe second shaft tubular section 130 of the second handle component 129.The gear wheel would preferably be chosen to mesh with the gear teethand the second handle component 129 could be advanced toward the firsthandle component 128 by rotating the gear wheel. A variety of otherdesign configurations could be utilized to control the relative locationbetween the first handle component and the second handle component asare well known to those skilled in the art.

FIGS. 13 through 17 show embodiments of a system for treating heartfailure. More specifically FIGS. 12 through 19 show how the placementcatheter is introduced and positioned in a patient and methods forplacing the interatrial valve in a patient. The interatrial pressurevent 100 is presterilized and packaged separately from the placementcatheter 111. Sterilization can be performed by exposing the device to asterilizing gas, such as ethylene oxide, by exposing the device toelevated temperature for an adequate period of time, by using ionizingradiation, such as gamma rays or electron beam or by immersing thedevice in a fluid that chemically crosslinks organic molecules, such asformaldehyde or glutaraldehyde and then rinsed in sterile water orsterile saline. For each of these sterilization methods, considerationmust be given to compatibility of the materials so device performance isnot adversely affected as a result of the sterilization process. Also,the packaging design and materials must be carefully considered with thesterilization procedure, post sterilization handling and storage,environmental exposure during storage and shipment, and ease ofhandling, opening, presentation and use during the procedure.

In embodiments, interatrial pressure vent 100 can be assembled usingcomponents that have been pre-sterilized using one of the above methodsor others that are well known and the final assembly may be accomplishedin an aseptic manner to avoid contamination.

In embodiments, the interatrial pressure vent 100 can be suppliednon-sterile and be sterilized around the time of use using one of theabove methods or by other methods well known by those skilled in theart.

Similarly, the placement catheter 111 may be pre-sterilized and packagedseparately from the interatrial pressure vent 100. Sterilization can beperformed using a similar method to the interatrial pressure vent 100 orusing a different method from the same choices or using some othermethod as is well known by those skilled in the art.

In embodiments, an interatrial pressure vent 100 and the placementcatheter 111 can be supplied pre-sterile and in the same package. Inanother aspect, the interatrial pressure vent 100 and the placementcatheter 111 can be preloaded and supplied pre-sterile.

Prior to insertion, the interatrial pressure vent 100 is preferablyfolded and stowed onto the placement catheter 111. This can beaccomplished in a sterile field and using aseptic techniques in thefollowing steps. First the interatrial pressure vent 100 is presented tothe sterile field and the placement catheter 111 is presented to thesterile field. Second, the interatrial pressure vent 100 and placementcatheter 111 are inspected for visible signs of damage, deterioration orcontamination. Third, the second handle component 129 of the placementcatheter 111 is retracted fully so the outer shaft 113 exposes the innershaft 112 to the maximum extent allowed. Fourth, the interatrialpressure vent 100 is positioned in the correct orientation over theinner shaft 113 of the placement catheter 111 with the inner shaft 113oriented through the center of the flow control element 104. Fifth, theflange segments 102 a-h and 103 a-h are folded away from each other andthe flange segments 102 a-h and 103 a-h and the core segment 106 arecompressed radially to fold the interatrial pressure vent 100 into asize and shape that will fit over and onto the waist section 120 of theinner shaft 112 with the distal ends 115 of flange segments 102 a-haligning with the proximal groove 114 of inner shaft 112.

In embodiments comprising a flange as described in FIG. 11A the flangesegments 102 a-h and 103 a-h are folded away from each other and theflange segments 102 a-h and 103 a-h and the core segment 106 arecompressed radially to fold the interatrial pressure vent 100 into asize and shape that will fit over the flange 3000 described on FIG. 11A.This folding may be accomplished with the aid of an insertion tool (notshown) that retains the interatrial pressure vent 100 in a stowedposition on inner shaft 112 and then advancing outer shaft 113 over thestowed interatrial pressure vent 100 and displacing the insertion tool,thereby leaving the outer shaft 113 completely covering the interatrialpressure vent 100 and mating with the distal tapered tip 140 of theinner shaft 112. In other embodiments, this can be accomplished by handusing the fingers of one hand to hold the distal ends 115 of the flangesegments 102 a-102 h in position at groove 114 of the inner shaft 112and advancing the outer shaft 113 over the inner shaft 112 enough tohold the flange segments 102 a-102 h in place. Completion of the loadingprocedure is accomplished by progressively advancing the outer shaft 113until it completely covers the interatrial pressure vent 100 as shown inFIGS. 11 and 11A. While the below discussion regarding placement of theinteratrial pressure vent uses the placement device shown in FIGS. 9-11as an example, the description on placement and the procedure thereforeis also meant to apply to embodiments where the inner shaft comprises aflange rather than grooves.

Positioning of the loaded interatrial valve 100 and placement catheter111 in preparation for implanting the interatrial valve 100 in thepatient can be accomplished by: first gaining vascular access; second,positioning a guidewire 121 in the right atrium of the patient; third,positioning an introducer (not shown) into the patients right atrium;fourth, locating the interatrial septum; fifth, advancing the introducerthrough the interatrial septum and into the patient's left atrium;sixth, advancing the guidewire 138 into the left atrium; seventh,retracting the introducer; eighth, advancing the loaded placementcatheter 111 and interatrial pressure vent 100 into position so thedistal end and approximately half of the stowed length of theinteratrial pressure vent 100 is protruding through the interatrialseptum and into the patient's left atrium as shown in FIG. 13.

In embodiments, positioning of the loaded interatrial valve 100 andplacement catheter 111 in preparation for implanting the interatrialvalve 100 in the patient can be accomplished by: first gaining vascularaccess; second, positioning a guidewire 138 in the right atrium of thepatient; third, advancing the loaded interatrial valve 100 and placementcatheter 111 over guidewire 138 by inserting the guidewire into andthrough lumen 136 and advancing placement catheter 111 into thepatient's right atrium; fourth, locating the interatrial septum; fifth,advancing the placement catheter 111 through the interatrial septum andinto the patient's left atrium so the distal end and approximately halfof the stowed length of the interatrial pressure vent 100 is protrudingthrough the interatrial septum and into the patient's left atrium asshown in FIG. 13.

Implanting interatrial pressure vent 100 into a patient can beaccomplished, once the loaded interatrial pressure vent 100 andplacement catheter 111 are in position as shown in FIG. 14, by first,retracting first handle component 128 toward second handle component 129while holding second handle component 129 until flange segments 103 a-hare fully uncovered as shown in FIG. 15, and as can be verified byvisualizing the markers 119 using fluoroscopy or using echocardiography;second, retracting the placement catheter 111 with partially deployedinteratrial pressure vent 100 toward the patient's right atrium untilthe flange segments 103 a-h are in contact with the left atrial side ofthe interatrial septum, as shown in FIG. 16, and as can be verifiedusing the same techniques mentioned or as can be perceived by the userbased on the resistance felt against further proximal movement of theplacement catheter 111; third, continuing to retract the outer sheath113 by retracting first handle 128 toward second handle 129 until theouter sheath 113 is retracted beyond the proximal end of groove 114 ofinner shaft 112 and also uncovers flange segments 102 a-h, at which timethe flange segments 102 a-h of interatrial pressure vent 100 will deployreturning to the preloaded geometry and capture the interatrial septumbetween the flange segments 103 a-h and flange segments 102 a-h as shownin shown in FIG. 18; fourth, the inner sheath is retracted through theflow control element 104 of interatrial pressure vent 100, into thepatient's right atrium as shown in FIG. 19; fifth the first handlecomponent 128 is advanced away from the second handle component 129 toreposition inner shaft 112 into the position relative to outer shaft 113it was in during placement and the placement catheter is removed fromthe patient and the procedure is completed.

In other embodiments, implanting interatrial pressure vent 100 into apatient can be accomplished, once the loaded interatrial pressure vent100 and placement catheter 111 are in position as shown in FIG. 14, byfirst, advancing second handle component 129 toward first handlecomponent 128 while holding first handle component 128 until flangesegments 103 a-h are fully uncovered as shown in FIG. 15, and as can beverified by visualizing the markers 119 using fluoroscopy or usingechocardiography; second, retracting the placement catheter 111 withpartially deployed interatrial pressure vent 100 toward the patient'sright atrium until the flange segments 103 a-h are in contact with theleft atrial side of the interatrial septum, as shown in FIG. 16, and ascan be verified using the same techniques mentioned or as can beperceived by the user based on the resistance felt against furtherproximal movement of the placement catheter 111; third, continuing toretract the outer sheath 113 by advancing second handle 129 toward thefirst handle 128 until the outer sheath 113 is retracted beyond theproximal end of groove 114 of inner shaft 112 and also uncovers flangesegments 102 a-h, at which time the flange segments 102 a-h ofinteratrial pressure vent 100 will deploy returning to the preloadedgeometry and capture the interatrial septum between the flange segments103 a-h and flange segments 102 a-h as shown in shown in FIG. 18;fourth, the inner sheath is retracted through the flow control element104 of interatrial pressure vent 100, into the patients right atrium asshown in FIG. 19; fifth, the second handle component 129 is retractedaway from the first handle component 128 to reposition inner shaft 112into the position relative to outer shaft 113 it was in during placementand the placement catheter is removed from the patient and the procedureis completed.

For a variety of reasons, it may be necessary or desirable to removeinteratrial pressure vent 100 and placement catheter 111 during any partof the procedure without further risk or injury to the patient. This ispossible as follows: if, for any reason, it is desired for the device tobe removed before outer shaft 113 is retracted and flange segments 103a-h are deployed, then the placement catheter 111 with interatrial valve100 can simply be retracted out through the same pathway as introduced.

If, following deployment of flange segments 103 a-h it is necessary ordesirable to remove the device, then the interatrial valve 100 can beretracted into the placement catheter 111 by advancing first handle 128away from second handle 129, while holding second handle 129 stationary,thereby advancing outer sheath 113 distally through the interatrialseptum and over the flange segments 103 a-h. In embodiments, radiopaquemarkers 118 placed in marker holes 109 are captured in groove 114 (seeFIG. 17) and cannot fit in the gap between waist 120 of inner shaft 112and inner surface of outer shaft 113, so as outer sheath 113 isadvanced, flange segments 103 a-h are forced to fold inward toward theirstowed position and are retracted back onto inner shaft 112 and withinouter sheath 113. Once outer shaft 113 is fully advanced, catheter 111can be retracted as shown in FIG. 17 to be removed out through theinteratrial septum and out through the same pathway as introduced.

FIG. 19A is an embodiment designed to enhance the retrievability of thedevice. The procedure for implanting the device is substantially similarto that which is described above; however, there are variations to theplacement catheter and the device, which will be described below. Asdiscussed in connection with FIGS. 7A through 7C, embodiments of theinteratrial venting device comprise at least one flange segment beinglonger than the other flange segments. The embodiment schematicallyshown in FIG. 19A preferably works with such embodiments having at leastone flange segment that are longer in relation to the other flangesegments; thus the segments shown in the RA have the same referencenumber as the longer segments in FIGS. 7A through 7C, i.e., 102L. Inembodiments utilizing the techniques shown in FIG. 19A, the opening 113a of outer sheath 113 of placement catheter is angled or has a moresurface area on one side relative to the other. The placement catheteris oriented during the procedure such that the angled opening (or theplane of the opening itself) is at an angle more normal to the septalwall 107. In the embodiment shown in FIG. 19A, that angle appears to bearound 45 degrees with respect to the septal wall 107, but any anglewhich provides an more normal angle with respect to the septal wall maybe used, and any opening which provides more surface area of the outersheath 113 on one side with respect to the other side may be used.Reference numerals 4000 through 4050 refer to steps in the processdescribed below. The process is largely similar to that described aboveor with respect to any well-known placement catheter system and process,therefore only the applicable differences will be described. As can beseen at steps 4000 through 4020, the placement catheter is positionedand the device is in the beginning stages of deployment. At steps 4030and 4040, the as the outer sheath 113 is retracted and on the RA side(or when the inner shaft is advanced while the outer sheath is on the RAside, which is not shown), the opening allows one of the longer flangesegments 102L to be deployed after other flange segments have beendeployed and are thus in contact with the septum 107. The at least onelonger flange segment 102L is retained in the placement catheter systemby way of the outer sheath 113, the length of which extends further onone side than the other due to the opening and thus covers the longersegment 102L while the other shorter segments have been deployed. Inthis way, the operator of the placement catheter can determine if theinteratrial device is in the proper position. If not, the operator canstill retrieve the device up until the last point prior to fulldeployment, i.e., when at least one of the longer flange segments (102Lfor example) is still retained in the placement catheter by the outersheath 113. If it is in proper position, the deployment may commence.

Another deployment embodiment is now described in connection with FIG.19B. This deployment embodiment may be used with any embodiment of theinteratrial vent described herein. Reference numerals 5000 through 5050refer to steps in the process described below. At step 5000, the LA sideof the device (generally referred to in this figure as 100) is deployedon the LA side of the heart. Further deployment is shown at step 5010and the outer sheath is retracted into the RA side of the heart, whichallows flow control element 104 to exit the placement catheter.Placement catheter is equipped with a balloon, which is in fluidcommunication, for example, with lumen 136 described above or guide wire138. The skilled artisan will appreciate other configurations in which aballoon catheter may be provided in the placement catheter system. Upondeployment of the LA side flange or shortly thereafter, balloon 139 isinflated (shown in step 5020). The inflation of the balloon optionallycoupled with a pulling-back motion of the placement catheter 111 holdsthe device 100 against the LA side of the septal wall 107 and therebyprevents the device 100 from dislodging during deployment and/or movingin a direction away from the septal wall. Step 5040 shows the fulldeployment of the device 100 while the balloon 139 is inflated. Whensatisfactory deployment is achieved, the balloon 139 is deflated and theplacement catheter system is removed (shown at step 5050). Otherembodiments that enhance deployment or retrieval of the device aredescribed throughout.

Now referring to FIG. 20, an interatrial pressure vent 200 is shown. Inembodiments, flange segments 202 a-h and 203 a-h can be formed withgraduating length to reduce interference between flange segments 202 a-hand 203 a-h during handling, folding and loading. In embodiments,radiopaque markers 218 and 219 protrude into the inner cylindrical shapeof the stowed position of the interatrial pressure vent and each flangesegment 202 a-h and 203 a-h differ in length by at least the width ofthe radiopaque markers 218 and 219. In embodiments, each flange segment202 a-h and 203 a-h differ in length by at least at least 1 mm. Inembodiments, each flange segment 202 a-h and 203 a-h differ in length byat least 2% of the overall length of interatrial pressure vent 200 inthe position shown in FIG. 20.

Now referring to FIG. 21, an interatrial pressure vent 300 is shown. Inembodiments, flange segments 302 a-h and 303 a-h can be formed withalternating length to reduce interference between flange segments 202a-h and 203 a-h during handling, folding and loading. In embodimentsradiopaque markers 318 and 319 protrude into the inner cylindrical shapeof the stowed position of the interatrial pressure vent 300 andalternating flange segments 302 a, c, e, and g are longer than flangesegments 302 b, d, f and h, and correspondingly, flange segments 303 b,d, f and h are longer than flange segments 303 a, c, e and g by at leastthe width of the radiopaque marker. In embodiments, alternating flangesegments 302 a, c, e and g are longer than flange segments 302 b, d, fand h and, correspondingly, flange segments 303 b, d, f and h are longerthan flange segments 303 a, c, e and g by at least 1 mm. In one aspectthe alternating flange segments 302 a, c, e and g are longer than flangesegments 302 b, d, f and h and, correspondingly, flange segments 303 b,d, f and g are longer than flange segments 303 a, c, e and g by at least2% of the overall length of interatrial pressure vent 300 in theposition shown in FIG. 21.

Referring now to FIG. 22 and FIG. 23, the body element 401 of aninteratrial pressure vent with integral thrombus filter and retrievalcone 442 is shown. In embodiments, conical struts 444 are affixed tobody element 401 at attachment points 446 and converge at apex 450. Inembodiments, conical struts 444 comprise single beams of similarmaterial to flange segments 402 and 403 and can be attached to the bodyelement or formed at the same time as the body element using techniquesdescribed in this specification, and can thus be integral with theremainder of the device. In embodiments the space between adjacentstruts 444 is about 2 mm. In embodiments, the space between adjacentstruts 444 is about 4 mm. As can be appreciated, conical struts 444 willprotrude into the right atrium of the patient after implant and spacesbetween conical struts will function to block the passage of solidmaterial larger than the space between adjacent struts 444. This willprovide the function of preventing emboli that are larger than the spacebetween the adjacent struts 444 from passing from the right atrium tothe left atrium.

Referring again to FIG. 22 and FIG. 23, in embodiments the shape of theconical struts 444 is not straight. In embodiments the shape of theconical struts 444 can be concave when viewed on end as depicted in FIG.22. In embodiments the conical struts can be curved in a direction awayfrom the chord formed between the apex 450 and the attachment points446. In embodiments there can be a hole 451 through apex 450 largeenough to receive a retrieval snare (not shown). It can be appreciatedthat conical struts 444 and apex 450 can be used to aid retrieval of theinteratrial pressure vent from a patient at some time after the implantprocedure using a method as follows: A catheter tube with an internallumen at least as large as apex 450 can be placed into the patient'sright atrium using standard techniques and imaging equipment. Aretrieval snare can be fabricated from the proximal end of a guidewirebent sharply by about 180 degrees and this snare can be inserted throughthe catheter tube and advanced into the patient's right atrium and, withthe assistance of fluoroscopy, advanced through hole 451 or aroundconical struts 444. Once the retrieval snare is engaged in this manner,it will be possible to retract the interatrial pressure vent byadvancing a catheter tube while holding slight tension on the snare andthereby guide the catheter tube over apex 450 and onto conical struts444.

As the catheter tube continues to advance, with some tension on thesnare it will be possible to force the conical struts inward, therebyforcing the flange segments 402 to begin folding inwards. When theconical struts are nearly completely in the catheter tube, the cathetertube can be held in a stationary position and the snare wire retractedagainst it, thereby causing the attachment points 446 between theconical struts 444 and the flange segment 402 to be retracted into thecatheter. Flange segments 402 can begin to be retracted into thecatheter at this point and the distal ends of flange segments 402 can bediverted toward the patient's left atrium but will also fold inward andinto the catheter. Once the flange segments 402 are inside of thecatheter tube, the snare can be held stationary and the catheter tubecan be advanced further, through the interatrial septum and over flangesegments 403. Once the flange segments 403 are retracted into thecatheter, the catheter and snare can be moved together to retract theinteratrial pressure vent into the patient's right atrium and outthrough the pathway through which it was introduced.

Referring now to FIGS. 24 and 25 an alternate embodiment of interatrialpressure vent 500 is shown. In embodiments, flow control element 504 maybe comprised of leaflets 541 a-c. Body element 501 may be comprised ofcore segment 506 and flange segments 502 a-1 and 503 a-1 (not fullyvisible in FIG. 25); the number of flange segments being a multiple ofthe number of leaflets. This configuration improves the symmetry ofstrain against the flow control leaflets and also improves theuniformity of motion by the flow control element to changes in bloodflow.

In some embodiments, the implantable devices in accordance with thepresent invention are designed to safeguard against portions of theflange of the inventive device that is to engage the near side of theseptum from entering into the space on the far side of the septum, e.g.,the left atrium when the delivery is being made from the right atrium.This safeguard is best understood by considering the implantable devicein its state of collapse along its longitudinal axis for percutaneousdelivery to the patient's heart. In the special case where the inventivedevice is delivered coaxially with the septal aperture, the safeguard isto provide that the longitudinal distance between the far end of thenear flange and the far end of the core segment of the implantabledevice is greater than the through-thickness of the septal aperture.More generally, this safeguard distance is the quotient of thelongitudinal length of the septal aperture into which the device isexpected to be implanted divided by the cosine of the angle thelongitudinal axis of the implantable device is expected to make duringdelivery in relation to the longitudinal axis of the septal aperture.

This safeguard is explained with reference to FIG. 79 which shows animplantable device 7900 in accordance with an embodiment of the presentinvention being delivered into an aperture 7902 in the septum 7904 of apatient's heart that divides the left atrium LA from the right atriumRA. At the stage of deployment shown in FIG. 79, the far flange 7906,the core segment 7908, and the far end of the near flange 7910 haveemerged from the delivery apparatus 7912. The longitudinal distance Lbetween the far end of the near flange 7910 and the far end of the coresegment 7908 is depicted in the drawing. The longitudinal axis A1 of thedelivery apparatus 7912 is shown as intersecting the longitudinal axisA2 of the septal aperture 7902 at an angle θ. Thus, for the case shownin the drawing, the length L is to be greater than the quotient of theseptal aperture through-thickness T divided by cosine θ.

In view of the fact that during deployment of the implantable device,the septal wall is in a dynamic state and the implantable device may notbe completely stationary, this minimum distance may be increased by afactor ranging between 1.1 and 2.0.

An embodiment of the implantable device, device 8000, in which thedevice is fully retrievable after deployment, is depicted in whole or inpart in FIGS. 80A-D. The device 8000 is configured to be collapsibleabout its longitudinal axis so that the device 8000 may be stored in adelivery apparatus for percutaneous delivery to a hole in the septalwall of a patient's heart. The device 8000 has a body element whichincludes a plurality of interconnected units 8002, a hub 8004 that isconnected to the near end of at least one of the units 8002, a firstflange 8006 that is at least in part formed by the junctions 8008 ofleft and right arm sections 8010, 8012 of adjacent units 8002, a secondflange 8014 that is at least in part formed by the far ends of at leastsome of the units 8002, and a core segment 8016. As is most readilyapparent from FIG. 80C, each of first and second flanges 8006, 8014comprises six individual segments. It is to be understood that therelational terms “right” and “left” are to be applied from the viewpointof an observer looking at the outside of the body element with the bodyelement oriented so that core segment longitudinal axis is orientedvertically and the hub is at the top.

In the embodiment depicted in FIGS. 80A-D, the device 8000 has six units8002, although it may have more or less than six in other embodiments.Each unit 8002 has extending from its near end a first diamond section8018 that connects at its far end to the near end of a second diamondsection 8020. Each unit 8002 also has a left arm section 8010 and aright arm section 8012, both of which connect at their respective nearends to the opposite sides of the unit's first diamond section 8018.Each of the left arm sections 8010 is connected at its far end to thefar end of the right arm unit 8012 of an adjacent unit 8002 to form ajunction 8008 that is one of a first set of junctions. Each of the units8002 also is connected at its second diamond section 8020 to therespective second diamond sections 8020 of its two adjacent units 8002to form junctions 8022 which are part of a second set of junctions.

The hub 8004 and the plurality of units 8002 in some embodiments of thepresent invention form an apex at what would be the near end of thedevice 8000 within the right atrium of the patient's heart whenimplanted. The hub 8004 in some instances is adapted to connect to adelivery and/or retrieval apparatus, e.g., such as a catheter-deliveredfilament or wire. In some instances, the hub 8004 is provided withinternal and/or external threads to form such a connection. In some suchembodiments, the hub 8004 is provided with a keyslot for making such aconnection.

The areas or portions of the device 8000 may have a constant width and aconstant through-thickness, such as width 8023 and through-thickness8024 of the cross-section of the arm of the second diamond section 8020shown in FIG. 80E. In some embodiments of the present invention,however, at least one of the width one area or portion varies inmagnitude between a high value and a low value wherein the low value isin the range of between 15 and 99 percent of the high value, and thethrough-thickness of one area or portion varies in magnitude between ahigh value and a low value wherein the low value is in the range ofbetween 40 and 99 percent of the high value.

In some embodiments of the present invention, the core segment 8016comprises one or more junctions 8022 which are part of a second set ofjunctions. In some instances, at least one of the junctions 8008, 8022of the first and second sets of junctions and/or at least one of thesecond diamond sections 8018 includes a radiopaque material, e.g., aradiopaque marker. In some instances, at least one of the junctions8008, 8022 of the first and second set of junctions and/or at least oneof the far ends of the units 8002 has a through-hole, e.g., through-hole8026, with such a through-hole in some instances being suitable toreceive a suture and/or a radiopaque marker.

In some embodiments of the present invention, when the device 8000 iscollapsed about its longitudinal axis for percutaneous delivery into thepatient's heart, the longitudinal distances between the far ends of thejunctions 8008 of the first set of junctions and the far end of the coresegment 8016 is greater than the quotient of the through-thickness ofthe septal aperture in which device 8000 is to be implanted divided bythe cosine of the angle the longitudinal axis of the device 8000 isexpected to make during delivery in relation to the longitudinal axis ofthe septal aperture. In some instances, when the device 8000 iscollapsed about its longitudinal axis for percutaneous delivery into thepatient's heart, the longitudinal distances from the connections of theleft and right arm units 8010, 8012 with the first diamond sections 8018to the far end of the device 8000 are at least three times thelongitudinal distances from the connections of the left and right armunits 8010, 8012 with the first diamond sections 8018 with the firstdiamond sections 8018 to the far ends of each of the junctions 8008 ofthe first set of junctions.

An embodiment of the implantable device, device 8100, in which thedevice is fully retrievable after deployment, is depicted in whole or inpart in FIGS. 81A-D. The device 8100 is configured to be collapsibleabout its longitudinal axis so that the device may be stored in adelivery apparatus for percutaneous delivery to a hole in the septalwall of a patient's heart. The device 8100 has a body element whichincludes a plurality of struts 8102, a hub 8104 that is connected to thenear end of at least one of the struts 8102, a first fork section 8106,a second fork section 8108, a third fork section 8110, a first flange8112, a second flange 8114, and a core segment 8116. As is most readilyapparent from FIG. 81B, each of first and second flanges 8110, 8112comprises six individual segments. It is to be understood that therelational terms “right”, “center”, and “left” are to be applied fromthe viewpoint of an observer looking at the outside of the body elementwith the body element oriented so that core segment longitudinal axis isoriented vertically and the hub is at the top.

Each of the struts 8102 is connected at its far end to the first forksection 8106, which has a left prong 8118, a center prong 8120, andright prong 8122. The center prong 8120 is, in turn, connected at itsfar end to the second fork section 8108, which has a left prong 8124 anda right prong 8126, each of which is connected at its far end to adifferent one of the third fork sections 8110. Each of the far ends ofthe left prongs 8118 of each of the first fork sections 8106 connects toa far end of the right prong 8122 of a different one of the first forksections 8106 to form a junction 8128 that is a member of a first set ofjunctions. The first flange 8112 includes at least some of the junctions8128 of this first set of junctions.

The core segment 8116 comprises one or more the third fork sections8110. Each of the far ends of the left prongs 8130 of the third forksections 8110 connects to a far end of the right prong 8132 of adifferent third fork section 8110 to form a junction 8134 that is amember of a second set of junctions. The second flange 8114 includes atleast some of the junctions 8132 of this second set of junctions.

The hub 8104 and the struts 8102 in some embodiments form an apex atwhat would be the end of the device 8100 which is within the rightatrium of the patient's heart when implanted. In some embodiments of thepresent invention, the hub 8104 is adapted to connect to a deliveryand/or retrieval apparatus, e.g., such as a catheter-delivered filamentor wire. In such embodiments, the hub 8104 is provided with internaland/or external threads to form such a connection. In some suchembodiments, the hub 8104 is provided with a keyslot for making such aconnection.

The areas or portions of the device 8100 may have a constant width and aconstant through-thickness, such as width 8145 and through-thickness8146 of the cross-section of strut 8102 shown in FIG. 81D. In someembodiments of the present invention, however, at least one of the widthand the through-thickness of one or more areas or portions of the devicevaries in magnitude as described herein. In some embodiments, at leastone of the width and the through-thickness of at least one of the struts8102 and/or at least one of the first fork sections 8106, the secondfork sections 8108, and the third fork sections 8110 varies in magnitudeas described above.

In some embodiments of the present invention, at least one of thejunctions 8128 of the first set of junctions and/or at least one of thejunctions 8134 of the second sets of junctions and/or at least one ofthe first fork sections 8106, the second fork sections 8108, and thethird fork sections 8110 includes a radiopaque material, e.g., aradiopaque marker. In some embodiments of the present invention, atleast one of the junctions 8128, 8134 of the first and second set ofjunctions has a through-hole, e.g., through-hole 8136, with such athrough-hole in some instances being suitable to receive a suture and/ora radiopaque marker.

In some embodiments of the present invention, when the device 8100 iscollapsed about its longitudinal axis for percutaneous delivery into thepatient's heart, the longitudinal distances between the far ends of thejunctions 8128 of the first set of junctions and the far end of the coresegment 8116 is greater than the quotient of the through-thickness ofthe septal aperture into which device 8100 is to be implanted divided bythe cosine of the angle which the longitudinal axis of the device 8100is expected to make during delivery in relation to the longitudinal axisof the septal aperture. This configuration helps to safeguard againstportions of the near flange, e.g., the first flange 8112, frominadvertently deploying on the far side of the septum. This is clarifiedby reference to FIGS. 82A-D.

FIGS. 82A-D is a series of schematic drawings which depict the beginningstages of the deployment of the device 8100 in an aperture 8202 of aseptum 8204, which separates the right atrium RA from the left atriumLA, by way of a delivery catheter 8206. In this set of drawings, forsimplicity of presentation, the longitudinal axis of the deliverycatheter 8206 is coaxial with the longitudinal axis of the aperture 8202so that the angle of their intersection is zero. Also for simplicity ofpresentation, the only parts of the device 8100 which are illustratedare planar projections of portions of the first flange 8112, the coresegment 8116, and the second flange 8114. In this embodiment, the farends of junctions 8128 of the first set of junctions of the device 8100are coincident with the far ends of the first flange 8112, and so, ofthe two items, reference will be made here only to the first flange8112.

FIG. 82A depicts the delivery catheter 8206 after its tip 8208 hasentered the left atrium LA. In the delivery stage depicted in FIG. 82B,the sheath 8210 of the delivery catheter 8206 has been partiallywithdrawn so that the far end of the second flange 8114 has begun toemerge from the delivery catheter 8206 and to bend radially outward fromthe longitudinal axis of the delivery catheter 8206. FIG. 82C depictsthe deployment at an instant later whereat the sheath 8210 has beendrawn back a bit further so that all of the second flange 8114, as wellas some of the core segment 8116, has emerged. Finally, FIG. 82D depictsthe stage at which the sheath 8210 has been drawn still further back sothat the far end of the first flange 8112 has begun to emerge and hasjust started to bend radially outward from the longitudinal axis of thedelivery catheter 8206. At this stage, the second flange 8114 has fullyformed and has seated itself against the left atrium LA side of theseptum 8204 and the core segment 8116 has fully emerged. From thisdrawing, by disregarding the slight outward bending of the first flange8112, it can be understood that for the device 8100 the longitudinaldistance L1 between the far end of the first flange 8112 and the far endof the core segment 8116, which in this drawing is coincident with thefar end of the septal aperture 8202, is greater than thethrough-thickness T of the septal aperture 8202. As mentioned, theintersection angle θ between the delivery catheter 8206 and thelongitudinal axis of the aperture 8202 in this case is zero, so thecosine of the intersection angle θ is equal to 1 and the quotient of thethrough-thickness T of the aperture 8202 and the cosine of theintersection angle θ is equal to the through-thickness T. See FIG. 79and its related discussion herein about the general case wherein theintersection angle θ is non-zero.

Another configuration for device 8100 for safeguarding against theinadvertent deployment of portions of the first flange 8112 on the farside of the septum is described with reference again to FIG. 81C. Inthis configuration, when the device 8100 is collapsed about itslongitudinal axis for percutaneous delivery into the patient's heart,the longitudinal distances B from the far end of each of the struts 8102to the far end of the device 8100 are at least three times thelongitudinal distances A from the far end of each of the struts 8102 tothe far end of each of the junctions 8128 of the second set ofjunctions.

Another embodiment of the implantable device, device 8300, in which thedevice is fully retrievable after deployment, is depicted in whole or inpart in FIGS. 83A-C. The device 8300 is configured to be collapsibleabout its longitudinal axis so that the device may be stored in adelivery apparatus for percutaneous delivery to a hole in the septalwall of a patient's heart. The device 8300 has a body assembly whichincludes a plurality of struts 8302, a hub 8304 that is connected to thenear end of at least one of the struts 8302, a plurality of first forksections 8306, a plurality of second fork sections 8308, a first flange8310, a second flange 8312, and a core segment 8314. Each of the firstand second flanges 8310, 8312 comprises a plurality of individualsegments, in this case eight individual segments. Note that each of thefirst and second flanges 8310, 8312 are annular flanges as each has itsflange segments arranged to form an annulus, similar to the annularflanges of other embodiments described herein.

The first flange 8310 comprises two or more of the struts 8302 eachhaving a u-shaped bend that forms one of the radially outer ends 8311 ofthe first flange 8310.

The near end of each of the struts 8302 optionally has a tab 8316. Eachof the struts 8302 is connected at its far end to one of the first forksections 8306. Each of the first fork sections 8306 has a left prong8318 and a right prong 8320. Each of the left prongs 8318 of the firstfork sections 8306 is connected at its far end to the far end of a rightprong 8320 of a different one the first fork sections 8306 at one of thesecond fork sections 8308. The core segment 8314 comprises the secondfork sections 8308. Each of the second fork sections 8308 has extendingfrom it a left prong 8322 and a right prong 8324. The far end of each ofthe left prongs 8322 of the second fork sections 8308 connects to a farend of a right prong 8322 of a different one of the second fork section8308 to form one of a plurality of junctions 8326. The second flangeincludes two or more of the junctions 8326.

The areas or portions of the device 8300 may have a constant width and aconstant through-thickness, such as width 8328 and through-thickness8330 of the cross-section of strut 8302 shown in FIG. 83C. In someembodiments of the present invention, however, at least one of the widthand the through-thickness of one or more areas or portions of the devicevaries in magnitude as described herein. In some embodiments, at leastone of the width and the through-thickness of at least one of the struts8302 and/or at least one of the first fork sections 8306 and the secondfork sections 8308, varies in magnitude as described above.

In some embodiments of the present invention, through-holes may providedin selected portions of the device 8300. In some instances thethrough-holes are suitable to receive a suture and/or a radiopaquemarker. Examples of such through-holes are through-holes 8332.

In some embodiments of the present invention, the segments of the firstand second flanges of the device expand in the same direction and/orcontract in the same direction. In other embodiments of the presentinvention, the segments of the first flange expand or contract in anopposite direction from the corresponding segments of the second flange.It is to be understood that these directional characteristics may applyto any device described herein.

FIG. 26 shows and alternate embodiment wherein the core segment 106 isovular rather than circular and thus the core segment is a cylindroid orelliptic cylinder rather than a simple cylinder. This embodiment is moreconducive to a bicuspid (or “duckbill”, bivalve, or two-leaflet)configuration for the flow control element. The duckbill configurationis generally referred to as flow control element 104 in this figure. Theinventors have found that the bi-valve configuration is able to openmore fully when coupled with a core segment in the shape of acylindroid.

FIGS. 27 and 27A show another embodiment of an interatrial device havingintermediate flange segments for a more secured fit against the septalwall. In embodiment, the device comprises, like many other embodimentsdisclosed herein, a core segment having an axial length and defining apassage. Like other embodiments disclosed herein there is a first annualflange and a second annular flange. The flanges themselves, similar toother embodiments disclosed herein, may be comprised of segments such as102 a-h and 103 a-h as shown in FIG. 6 by way of a non-limiting example.However, embodiments with an intermediate flange comprise a flange thatcontacts the RA or LA side of the septum for better adherence andpositioning of the device within the atrial septum. Thus, theintermediate flange may be disposed between the first annular flange andthe second annular flange along the core segment axial length Like otherflanges disclosed herein the intermediate flange may be annular, and maycomprise a plurality of flange segments. The flange segments of theintermediate flange have substantially similar lengths and, inembodiments, those lengths are less than the lengths of the flangesegments of the first and second annular flanges. In embodiments, theintermediate flange segments are part of another a third annular flangesituated on the same side of the septal wall as one of the otherflanges. Reference numerals 6000 through 6040 refer to steps in thedeployment of such an embodiment and will be discussed in connectionwith the structural features of the embodiment to illustrate thisembodiment's utility and operation. The deployment process is similar tothose described above, and to any commonly-known catheter based deliveryprocess and as such the details of the process will not be discussedherein. Steps 6000 to 6020 show the deployment process steps proceedingin much the same manner as described herein. At step 6030, intermediateflange segments 602 and 604 of intermediate (or third) annular flangeare deployed on the RA side. In this embodiment, intermediate flangesegments 602 and 604 are shorter than the majority of the flangesegments of the RA-side flange. As such, segments 602 and 604 aredeployed prior to other longer segments and contact the septal wall 107at points closer to the septal opening than the contact points of thelonger segments. In this manner, the intermediate segments 602 and 604(and the flange which they comprise) provide increased stability of thedevice. Any number of intermediate segments may be used although it ispreferable to have at least two. As with other embodiments, thestiffness of the intermediate segments may be altered so as to differfrom other flange segments of the device to avoid damage to the septalwall, i.e., lesser stiffness/greater flexibility, or to provideincreased stability, i.e., greater stiffness/lesser flexibility. Thechoice of stiffness/flexibility variations must be balanced against thedesired goals.

FIG. 27A is a side elevational view of embodiment discussed inconnection with FIG. 27. In FIG. 27A the pressure venting device in itsstowed configuration. Flanges 102 and 103 are shown with the flangesegments that comprise them (flange segments not individually labeled).Core segment is again shown as 106. At a point between the end of thecore segment 106 and proximal end of the RA side flange segment 102, theintermediate segments (collectively referred to as 600) emerge.Intermediate segments may be integral with the venting device orattached thereto in the manners described above.

In other embodiments, the flow control element is configured to directthe blood flow in a desired direction. FIGS. 28A through 28C show suchembodiments. In FIG. 28A interatrial device 100 is shown implanted inthe atrial septum 107 of the heart in the same manner as shown inFIG. 1. Flow control element 104 is configured to aim the flow, shown inthis figure as in the direction toward the superior vena cava. FIGS. 28Band 28C show a more detailed view of embodiments that enable the flow tobe directed in a desired direction. As shown in FIG. 28B, flow controlelement may comprise a baffle-like flange 104 a that extends at adownward angle and in the corresponding direction. In use, suchembodiment directs the flow downward. FIG. 28C shows an embodiment wherethe flow is directed upward. The valve material (e.g. material forleaflets) can be sized and secured to the 100 in manner to direct theflow. For example, the flow control element may contain a curved tubularmember whose opening points toward the direction of flow, or the flowcontrol element may otherwise comprise an opening directed at the areaof interest. In embodiments with baffles, the stiffness of the baffle104 a may be varied, for example, made stiffer. The length of the bafflecan also be varied depending on the desired flow direction. The bafflecan be a separate member attached to the flow control element or it maybe made of the material and/or integral with the remainder of the flowcontrol element.

FIGS. 29A through C show exit profile shapes of the flow control element104. In these figures, the flow control element 104 is being viewed fromthe RA side and thus the direction of flow is understood to coming outof the page at an angle substantially normal to the page. If the flowcontrol element is a valve as described herein, folding and suturingpatterns may be employed to achieved these exit profile shapes. In otherembodiments, the end of the flow control element may be provided with aplate, or a partially frustoconical end piece, having an openingdefining the two-dimensional shape shown in the Figure. The skilledartisan will appreciate that other exit profile shapes may be fashioned.The selection of an exit profile shape may provide advantages such asdirecting flow, preventing thrombi from moving across the septal divide,and/or reducing injury to surrounding tissue.

Another embodiment is shown in FIG. 30. In this embodiment, the coresegment 106 and flanges 102 and 103 of the device are substantiallysimilar those described herein. Instead of the flow control elementsdescribed above (or in addition thereto) a tube-like member 700 issecured to the core segment 106. The tube member 700 is attached to thecore segment 700 in a manner to allow the RA end of tube to extend intothe RA in an axial direction, thus the tube's length must be sufficientto extend a distance into the RA. It has been found that the tube 700configured in this manner prevents embolic particles from entering thetube and crossing over the septal divide into the LA. The distance thatthe tube 700 extends into the RA and beyond the plane of the RA-sideflange opening (indicated by dotted line) should be at least a 1 mm butmay be up to 2 cm in preferable embodiments. Even at relatively shortlengths (such as where the tube extends only a few millimeters into theRA), the inventors have noted the surprisingly unexpected result of areduction of embolic particles passing through. This is due to, in part,the tendency of embolic particles to collect along the surface of theseptal wall and move toward the septal opening (or opening of animplanted device) with each cycle of the heart. By extending away fromthe septal wall 107, the tube provides an effective barrier to theembolic particles that would otherwise travel toward and possiblythrough the septal opening.

FIG. 31 depicts a first embodiment of a mounting and loading tool usefulfor placing the some embodiments of prosthesis, namely ones having nostruts meeting at an apex such as those similar to the embodimentsdepicted in 2, 4, 5, and 6 for example, onto a catheter or otherdelivery device for delivery in vivo to a patient. In this embodiment,mounting tool 2001 includes a base plate 2002 with orifices 2003 forsecuring other components as shown with fasteners 2004 and pin 2009. Theprincipal component is a loader body 2014, mounted via the outer twofasteners and orifices as shown. A mounting platform 2023 is mounted inthe center of the loader body via the third orifice and pin 2009.Mounting platform 2023 includes a lower orifice 2026 for mounting to theloader body via the middle loader body orifice with pin 2009. Mountingplatform 2023 also includes a slotted cam surface 2024. Pivot 2029mounts to the loader body 2014 via pivot pin 2028 through pivot orifice2030 and loader body orifice 2016. Pivot 2029 and lever 2031 mount onthe left side of loader body 2014 below the side doors 2020, as seen inFIG. 31. Movement of pivot 2029 and lever 2031 on the cam surface allowsa user to raise and lower the mounting platform. The two oppositepositions of the mounting platform are the lower and upper positions,achieved by rotating the pivot to the desired position. In otherembodiments, the cam surface may simply be a slot or groove in the sideof the mounting platform 2023.

The loader body 2014 also mounts the other components of the device. Theloader body includes internal side channels 2018 for mounting two sidedoors 2020 and also includes vertical bores 2015 and a vertical sidechannel 2019 for mounting top plate 2005. The side doors 2020 include acentral orifice 2027 in the shape of a semicircle, for closing againstthe prosthesis, discussed below. The side doors include shelves 2021 oneither side for riding against the channel 2018 of the loader body. Theside doors each also include a retaining pin 2022. The pins protrudethrough side windows 2017 in the loader body and allow the side doors toslide within the loader body while preventing their complete removalfrom the assembly.

Top plate 2005 includes a top surface 2006, an adjustable internal iris2011, which functions much like the iris in a camera. The iris hassections that adjust inward and outward to open and to close the centralopening of the iris. The adjustable iris decreases the area of theopening and closes in a manner that allows the top section of theimplantable device to rest on top of the partially or full closed iris.Opening and closing of the iris is controlled by control lever 2013. Thetop plate includes two vertical rods 2007 for mounting in the verticalbores 2015 of the loader body and also includes a vertical side guide2008 with an elevating mechanism 2010 actuated by a top thumbwheel 2012.Raising and lowering via the elevating mechanism allows the user toraise and lower the iris and thus adjust the separation of the left andright flanges of the prosthesis with the iris.

The mounting and loading assembly is used in the following manner. Theloader body is positioned conveniently for the user, with the top plateremoved and with the doors open. A prosthesis, such as prosthesis 100,is placed on the loading platform, with the left atrium legs or flangefacing downward and with the loading platform in the lower position. Thedoors 2020 are then closed, with the mounting platform still in thelower position, thus placing the left atrium flange below the doors. Themounting platform 2023 is then raised to its upper position by rotatingpivot 2029, causing the lower portion (left atrium flange or legs) to bepressed against the under side of the doors 2020. While not shown inFIG. 31, this movement causes the legs of the left atrium flange to beradially spread out.

At this point, the top plate is assembled to the mounting and loadingtool and a catheter, such as one of the catheters depicted above inFIGS. 10-12, and also described above, is introduced though the centerof the prosthesis. The portion inserted includes the catheter tip and aportion of the catheter control wire connected to the tip. The positionof the catheter is adjusted so that the right atrium ball (“RA ball”) orother retention device is vertically aligned with the right atriumflange, as discussed above with respect to FIG. 11A. The iris is thenpartially closed. Vertical alignment may be achieved by raising the topplate 2005 using handwheel 2012. With the doors 2020 closed and the leftatrium flange trapped below the doors, raising the top plate willstretch the prosthesis, separate the left and right atrium flanges, andalso stretch the prosthesis over the catheter. In one embodiment, thediameter of the orifice made by the two half-circular cut outs 2027 ofthe side doors is about equal, or slightly less than, a diameter of thecatheter intended for use as a delivery device for the prosthesisdiscussed herein. The diameter may range from about 3 mm (9 Fr) to about7 mm (21 Fr).

As the iris is raised, the upper (right atrium) flange will approach theretention device, such as the RA ball and the outer sheath of thecatheter. The iris may continue to be closed while the top plate israised, thus bringing the RA flange into contact with the RA ball. Ifthe mounting platform 2023 has not been fully raised, it may also beraised gradually during this process. The entire sequence may beachieved by sequential use of the mounting platform 2023 and pivot 2029,the iris 2011 and handle 2013, and the elevating mechanism 2010 andthumbwheel 2012. When the RA flange has closed over the RA ball, theouter sheath may then be brought over the RA flange, securing the end ofthe prosthesis in the outer sheath. At this point, the iris 2011 may beopened along with doors 2020 and the catheter and prosthesis removedfrom the mounting and loading tool. The inner wire, firmly attached tothe catheter tip and RA ball, is then retracted, pulling the centralportion of the prosthesis and the LA flange into the outer catheter.

The catheter is then processed as discussed above, including assembly toa control device or handle, packaging, and so forth. This process isdesirably performed in a sterile environment, with all components,tools, fasteners, and so forth, scrupulously clean and sterile beforeand during all steps of the process. The mounting and loading tooldepicted in FIG. 31 and described above is desirably made from an inert,lubricious and medically-acceptable plastic material, such as afluoropolymer, fluorinated ethylene-propylene, PTFE, UHMWPE, acetal,polycarbonate, and so forth.

In addition to the mounting and loading tool discussed with respect toFIG. 31, there are other embodiments for mounting a prosthesis and forloading a prosthesis onto a catheter or delivery device. Additionalembodiments of useful tools are discussed below. In the discussionbelow, FIGS. 32-34 concern a discrete mounting tool, while FIG. 35concerns a separate tool for loading a mounted prosthesis onto a loadingtool.

FIG. 32 depicts a mounting tool 2500 useful for mounting a prosthesisfor relieving intracardial pressure for a mammal, such as a human. Themounting tool includes four principal components. The principalcomponents include a mounting plate 2501, a star-shaped cutout plate2511, a lower flat disc 2521, also known as a right atrium or RA disc,and an upper counterbored disc 2531, also known as a left atrium or LAdisc. The four components are used and stacked in the manner depicted inthe drawing, in combination with a prosthesis mounted on the tool. Allfour components are desirably made from a lubricious, non-allergenic,medically-acceptable plastic, such as a fluoropolymer, fluorinatedethylene-propylene, PTFE, UHMWPE, acetal, polycarbonate, and so forth.

Mounting tool 2500 includes mounting plate 2501 having a cylindricalbottom disc 2503, the disc having a central raised portion 2505 and anadditional raised portion 2507 atop the central raised portion. Plate2501 also includes a plurality of inserts 2502 for attracting andjoining with a similar number of inserts in cutout plate 2511. Theinserts may be magnets or a combination of magnets andmagnetically-attractive materials.

Star-shaped cutout plate 2511 includes a flat top surface 2512 with acutout in a general shape of a star 2515. While the cutout has thegeneral shape of a star, it is understood that the shape need not be aperfect star with perfectly equal sides and perfect angles between alllegs or sides of the star. For example, the tips and corners of eachpoint of the star are rounded rather than sharp. This avoids scratchingthe prosthesis and also avoids any scratching of personnel assemblingthe prosthesis to a catheter. A cutout in a general shape of a star issufficient to accomplish the task described herein. The skilled artisanwill appreciate that the shape would be appropriate for accommodatingthe shape of the device.

The bottom surface includes a counterbore 2514 for most of the entirebottom surface. A counterbored surface typically has an abrupt orright-angle termination, such as achieved by molding or by machiningwith an end-mill or other flat-bottomed tool. The counterbored surfaceis preferable to a more gradual change, such as a funnel-shapedcountersink or angled approach. As discussed below, the counterboredsurface of the cutout plate is used to mount the cutout plate to aloading tool. Thus, having the walls of the counterbore straight ratherthan angled is helpful, because with sufficiently close tolerances, thecounterbore aids in firmly securing the cutout plate to the loading toolused. It is possible, however, that angled walls, i.e., a countersink,may be used instead. Cutout plate 2511 also includes a plurality ofinserts 2502 matching the plurality of inserts in mounting plate 2501.In one embodiment, the inserts are polar magnets, i.e., N-S magnets withthe poles arranged so that the discs can only be joined in one way.

For example, mounting plate 2501 may have eight N-S magnets molded intothe plate with the north poles on the top side, with the raisedportions. If cutout plate 2511 has the magnets similarly mounted, northpoles on top, south poles on bottom, then the south poles on the bottomof cutout plate 2511 will attract the north poles on the top side ofmounting plate 2501, and the two plates may be joined. Because of thepolar orientation, there will be no magnetic attraction if one tries toassemble the discs in the incorrect manner, i.e., with the counterboredsurface on top. In another incorrect orientation, with the cutout plate2511 below mounting plate 2501, the plates will be magneticallyattracted for assembly, but the star-shaped feature 2515 will bepositioned away from the raised portions 2505, 2507. A user will not beable to position the prosthesis on the mounting tool using both theraised surfaces and the star-shaped cutout. Thus the mounting plate 2501and the cutout plate 2511 have been designed for assembly and forfool-proof assembly.

Right atrium disc or lower flat disc 2521 is made as a two-partassembly, a right half 2522 and a left half 2523. There is a centralorifice 2525 and the disc has a chamfer or bevel 2526 on its side. Eachside of each half has three bores 2527 within the disc and perpendicularto a radius of the disc, the three bores on each side used to assemblethe halves. In one embodiment, the outer two bores are used for magnetsto attract the halves together and the central bore is used for a dowelto align the halves. Thus, in one embodiment, right half 2522 has threebores 2527 as shown, the central bore being merely a void for acceptinga dowel from the left half, and the two side bores filled with twonorth-south magnets with the south poles facing outward. Left half 2523has three bores 2527 on each side, the central bore on each side filledwith a protruding dowel 2528 and the two side bores filled with twonorth-south magnets with the north poles facing outward. Use of thedowel and the void may be considered as a male-female joint. When thetwo halves are brought into contact, the opposite poles of the magnetswill attract and the two halves will be firmly joined.

The left atrium disc 2531, also known as the upper counterbored disc, isalso formed as two halves, right half 2532 and left half 2533.Counterbored disc 2531 has a counterbore 2534 on top, the counterboredor void portion removing material from a majority of the top surface.There is a chamfer or bevel 2536 on the side of the disc toward thebottom, such that when counterbored disc 2531 is assembled with lowerflat disc 2521, there is a “V” in profile, the “V” formed by the bevelsor chamfers on the two discs. Counterbored top disc 2531 also has acentral bore 2535 of about the same diameter as central bore 2525 oflower flat disc 2521. Each side of the halves includes three bores 2537within the disc, the bores perpendicular to a radius of the disc. Thebores are voids for accepting devices for joining the two halves, asdiscussed above for the lower flat disc. In one embodiment, the centralbores include a dowel and a void for aligning the two halves, while theouter bores include magnets 2502 with oppositely-facing poles forattracting each other. The dowel and void function for assembly as a taband a slot in both the right and left atrium discs 2521, 2531. The boresmay themselves be considered a slot, for use with a dowel, a tab, amagnet or a magnetic material. The tabs may be made of a plasticmaterial or may be made of durable stainless steel or othernon-corroding, medically-acceptable material.

In other embodiments for the side bores on either the lower plate 2521or the upper counterbored disc 2531, the inserts could include magnetson one half and steel or iron bars on the other half, or one magnet andone steel bar on each half, with a facing magnetically-attractive metaland magnet on the other half.

In one embodiment, the lower flat disc 2521 may be made a differentheight than the height of the upper counterbored disc 2531. Thedifference in heights makes it unlikely that an improper assembly couldoccur between one half of the lower flat disc and one half of the uppercounterbored disc. In one embodiment, the magnets of the halves with thecentral dowels may be assembled with the north poles outward, while themagnets of the halves with the central voids may be assembled with thesouth poles outward. This would make mis-assembly of the lower flat disc2521 and the upper counterbored disc 2531 very difficult, since twopieces with dowels (male portions) would be impossible to join. Whilethe two pieces with voids may be magnetically attractive and may join toform a mis-assembly, there would only be one assembled disc, since thetwo halves with the dowels could not be joined. Thus, use of the magnetsand dowels makes assembly of the discs virtually error-proof.

Mounting tool 2500 is used to orient implantable devices that requirethe loading tool for placement in the loading tool, as discussed below.In practice, a prosthesis for placement in a patient's heart is placedon the mounting plate 2501. In one embodiment, a right atrium (RA)flange is placed on the central portion 2505. The star-shaped cutoutplate 2511 is placed atop the mounting plate 2501, with the points ofthe star placed atop the flange joints of the RA flange, thus lockingthe prosthesis in place with the oppositely-facing magnets. The leftatrium (LA) flange and the barrel, or central portion of the prosthesis,now stand above the raised portions 2505, 2507 of mounting plate 2501.The right atrium disc 2521 is now joined to the assembly between theright atrium flange (lower portion) of the prosthesis and the leftatrium flange (upper portion) by bringing the two halves together, suchthat the bevel 2526 is on the upper side of the disc 2521.

The left atrium disc 2531 is then added to the assembly atop the rightatrium disc, also by bringing the two halves together. In this instance,bevel 2536 of the left atrium disc 2531 faces downward. The chamfers orbevels of the two discs are thus adjacent when the mounting tool 2500 isassembly correctly, the bevels together forming a “V” which will be usedlater by the loading tool, as discussed below. The mounting plate 2501and the star-shaped cutout plate 2511 may then be removed. When theprosthesis has been placed correctly on the mounting tool and themounting plate and cutout plate are removed, the left atrium flangeprotrudes from the left atrium disc and the right atrium flangeprotrudes from the right atrium disc, as seen in FIGS. 33-34.

The mounting tool is depicted in FIG. 33 after it has been assembledwith a prosthesis 100. The mounting tool includes mounting plate 2501with cutout plate 2511 atop the mounting plate, and with right atriumdisc 2521 atop left atrium disc 2531. In this figure, prosthesis 100 ismounted with left atrium flange 103 visible on top. Note the counterbore 2534 visible in the left atrium disc 2531. This is theconfiguration immediately after the prosthesis has been mounted and theleft and right atrium discs have been inserted to separate the left andright atrium flanges. Note also that bevels 2526 and 2536 are adjacent,forming a V when seen from the side.

In FIG. 34, the mounting and cutout plates have been removed and theassembly 2560 has been inverted, with right atrium disc 2521 atop leftatrium disc 2531 and with the right atrium flange 102 of the prosthesis100 on top. Note that the right atrium disc 2521 is flat and has nocounterbore on the side seen in this view.

After the prosthesis has been mounted, a loading tool may be used toassemble the prosthesis and place it into a catheter or other deliverydevice. A loading tool useful in this process is depicted in FIG. 35 andis herein described.

Loading tool 2600 includes a base plate 2601, side door supports 2611and 2621, a central column 2641 and a travel subassembly 2650. The baseplate, side door supports and central column each mount to the baseplate via fasteners 2604, as shown. In one embodiment, the fasteners maymount through the bottom and the heads may reside in countersunk orcounterbored recesses in the bottom of the base plate. The base platealso includes a travel control mechanism or thumbwheel 2606, includingtravel screw 2607 and spacer 2608. In this embodiment, the travelcontrol mechanism 2606, and the thumbwheel travel adjuster are mountedwithin the base plate, and a portion of the handwheel protrudes througha side of the base plate. Rotating the thumbwheel allows one to advanceor retract travel screw 2607 and thus raise or lower travel subassembly2650.

Side doors 2631 are identical and reside on side door supports 2611,2621. Main doors 2660 are also substantially identical and reside ontravel subassembly 2650. In one embodiment, door supports 2611, 2621each include a top shelf 2613 for capturing a side door and allowing itto ride back forth, to and fro. In addition, door supports 2611, 2621also each contain a travel stop or pin 2615, 2625. The pin stands in agroove 2637 within the side door, the pin limiting travel of the door tothat allowed by the grooves, e.g., the half-way mark of the centralcolumn 2641 and its concentric top surface 2643, on the one side, andretreat from the central column in the opposite direction whenappropriate. In this manner, the side doors can slide back and forthsymmetrically to meet each other. The side doors have a taper 2633 ontheir front, as well as a half-circular cutout 2635 on the front. Eachside door 2631 also has a vertical pin 2636 for ease of moving the doorback and forth and also limiting the forward travel, when the pintouches the shelf 2613. In one embodiment, the diameter of the orificemade by the two half-circular cut outs is about equal, or slightly lessthan, a diameter of a catheter intended for use as a delivery device forthe prosthesis discussed herein. The diameter may range from about 3 mm(9 Fr) to about 20 mm (60 Fr).

Main doors 2660 mount atop the travel subassembly 2650 via main doormounts 2651, 2652. The main doors slide back and forth in a mannerorthogonal to the side doors. In this embodiment, the main doors aresomewhat larger than the side doors and are used to compress theprosthesis to a diameter suitable for a catheter with a similarlydesirably small diameter for delivery to a patient. The front portion ofthe each of the main doors thus includes a transition 2664 to a frontalsemicircular arc 2665 and a semicircular bore 2666 with a radiusconsistent with such a small diameter. In one embodiment, the desireddiameter is about 3.3 mm or 10 Fr, and the radius of the front bore isthus about 1.65 mm. In other embodiments, the radius is from about 1 mmto about 4.5 mm, to accommodate delivery catheters from about 2 mm toabout 9 mm, and for catheters with a similar diameter.

The travel subassembly 2650 mounts to the loading tool via an internalthreaded bore 2657 that interfaces with threaded screw 2607. Movement ofthe thumbwheel 2606 moves travel subassembly 2650 up and down asdesired. Travel assembly 2650 includes door mounts 2651, 2652 includingtongues 2654 atop the mounts and pins 2653 for limiting travel of themain doors. The main doors 2660 are substantially identical and includea groove 2661 along their length of their bottom. Tongues 2653 ridewithin grooves 2661 of the main doors.

The main doors also include locking pins 2663. Each pin may be used tolock the main door 2660 into the closed position by closing the doorfully and depressing the pin to engage orifice 2655 in door mounts 2651,2652. The pins 2663 may also be used to restrain each door away from theclosed position by opening the main doors and depressing the pinsoutside travel subassembly 2650 so that further inward travel is notpossible with the pins depressed. Central column 2641 with mountingsurface 2643 mounts to the base plate 2601 via a central orifice 2645and a fastener from below the base plate. The central column ispositioned symmetrically within orifice 2656 of the travel subassembly2650. The central column and the mounting surface are stationary, whilearound them the travel subassembly 2650 travels vertically and sidedoors 2631 and main doors 2660 move horizontally.

The loading tool is used in the following manner, in one embodiment.Other embodiments and other methods may also be used.

The side doors and main doors are opened to their full open positionsand the mounted prosthesis assembly 2560 described above is placed ontocentral column top surface 2643, with the right atrium flange or legs upand the left atrium flange down. Note that in this configuration, theleft atrium disc 2531, which is the disc with the large counterbore2534, faces downward. In one embodiment, the counterbore is sized andoriented to fit precisely onto top mounting surface 2643 of the loadingtool 2600, discussed below. Top surface 2643 is the mounting or loadingsurface for placing the mounted assembly 2560 into the loading tool2600.

Once the mounted assembly 2560 is placed into the loading tool 2600, thetravel subassembly 2650 is raised or lowered so that the side doorsalign with the “V” formed by the bevels or “V” of the mounted assembly.The side doors 2631 are then closed, bringing the tapered front portionsof the side doors into contact with the “V” and urging apart the leftatrium and right atrium discs of the mounting tool. The main doors 2660are then closed against the side doors 2631.

Once this has been accomplished, a delivery catheter 2040 is assembledto the prosthesis, as depicted in FIG. 36. A clear loading tube 2561 ismoved over the outer sheath 2563 and the tip (not shown in FIG. 36) ofthe catheter 2040 is inserted through the central bore of the mountedassembly 2560. Visible in FIG. 36 is the inner sheath 2565, innercontrol wire 2569 and right atrium ball 2567. As seen in the figure, theright atrium ball 2567 should be aligned with the right atrium flange102. The thumbwheel 2606 is then adjusted so that the main doors 2660are above the side doors 2631, such that the main doors 2660 can close.As the closed main doors are raised using thumbwheel 2606, the rightatrium disc 2521 will rise, and the right atrium flange 102 will beginto lengthen axially and compress radially. It may be advantageous toinsure that no legs or struts of the flange are intermingled or caughtin the disc or the doors as the doors rise. Thumbwheel 2606 is used toraise the main doors while the catheter is held in a position thatallows the right atrium flange to close around the right atrium ball2567. When this operation has been correctly accomplished, the legs orstruts of the flange are evenly and tightly spaced around the rightatrium ball or flange.

The prosthesis is now brought into the catheter. In one embodiment, thefollowing procedure is used. The RA ball acts as a compression device,compressing the right atrium flange. After the right atrium flange isfirmly compressed around the right atrium ball, the outer sheath 2563 isheld firmly while the inner sheath 2565 and control wire 2569 are pulledback. This pushes outer sheath 2563 over the right atrium flange andball 2567. The ball 2567 should be pulled into the outer sheath 2563 sothat it, and the right atrium flange, are no longer visible. The travelassembly 2650 is now lowered, using the thumbwheel, until it justtouches the side doors 2631 (not shown in this view). Both sets of doorsare opened and the catheter 2040 and left and right atrium discs 2631,2621 are removed from the loading tool 2600. The left and right atriumdiscs are then removed from the catheter by pulling them apart.

The left atrium flange is now lengthened axially and compressedradially. In one embodiment, the clear loading tube 2561 has a largerdiameter than the outer sheath 2563. The clear loading tube 2561 is slidover the left atrium flange 103, pushing the left atrium flange legstogether. The clear loading tube should be slid forward or distallyuntil it completely covers the prosthesis. The control wire 2569 is thenpulled proximally, pulling the inner sheath 2565 and pulling theprosthesis into outer sheath 2563. The clear loading tube 2561 is thenremoved. The above mounting and loading procedures are accomplished in asterile environment. Alternatively, the devices and components may besterilized or re-sterilized after assembly.

Any other desired components, such as an outer shipping sheath, may thenbe added. In one embodiment, an outer shipping sheath is added in asterile manner, as shown in FIG. 37, over the outer sheath 2563. Sterileouter shipping sheath 2571 with connector 2573 and visible cap 2575 isadded over the outer sheath 2563 in such a way that inner sheath 2565,right atrium ball 2567 and right atrium flange 102, the central portionof prosthesis 100, left atrium flange 103, inner control wire 2569 andtip 2570 are visible from the outside of sheath 2571. In the embodimentshown, the prosthesis, including the right atrium flange 102 and rightatrium ball 2567, has been advanced using the control wire 2569, or theouter sheath 2563 has been retracted, to allow visibility from theoutside of the device. The catheter 2040, with the prosthesis loaded andready for inspection and deployment, is now ready for shipment to ahospital or other care-giving institution.

Implanting and Deploying the Prosthesis

With this embodiment, and in this configuration, a physician canimmediately inspect the prosthesis and determine whether the prosthesisis suitable for implantation into a patient. For example, the physiciancan immediately inspect, without even opening the outer package, whetherthe legs or struts of the right atrium flange are intertangled. Thephysician can also determine whether the left atrium flange or centerportion are also suitable for implantation into the patient.

As noted, the shipping sheath is advanced over the outer sheath 2653 ofthe delivery of deployment catheter 2040. Accordingly, the prosthesis100 remains within the outer sheath at all times during shipping andduring removal of the shipping sheath. In some embodiments, the outercatheter is connected at its proximal end to an irrigation system,described below, suitable for irrigating the outer sheath, and thus theprosthesis, with sterile fluid, a radiopaque dye, or other desiredsolution. A physician can thus remove the shipping sheath, flush theprosthesis with sterile solution using the irrigation system, and movethe prosthesis back and forth within the outer sheath. This allows thephysician to remove any possible bubbles from the device and thecatheter, at the same time allowing the physician to test the level ofeffort required to advance and retract the prosthesis or the outersheath with respect to each other.

More Control Systems for Deploying the Prosthesis

A control system, including a control device or handle, and anirrigation system, may also be usefully employed with the catheterdescribed above. One example of a control system or handle was givenabove in FIG. 12, and also explained. Another example is depicted inFIGS. 38A and 38B, control system 2700, including control handle 2701and irrigation system 2720. The control handle 2701 includes a housingor grip 2713 and a control trigger 2715 for a user to retract the outersheath or advance the inner control wire. The tension or pull requiredfor the trigger 2715 is set with trigger spring 2731. Thus, spring 2731controls the force needed by the user to deploy the prosthesis, i.e.,the force required to release the implant onto the septal wall.

The inner control wire is grounded to the control handle through firstplate 2711 via the flange 2041 of the inner control wire and may also besecured with adjustment screw 2715. The position of the first platewithin the handle is set by a pin and bore, or set screw or otherarrangement (not shown). The second plate 2717 is connected to the outersheath and the irrigation system, which are secured to the second platevia connector 2722. The second plate is connected via a slot (not shown)on its rear face to a pin (see FIG. 38B) on the actuation mechanismwithin the handle. The first and second plates 2711, 2717 have slots ormortises on their rear faces for riding on a tenon or shelf 2716 on theside of the front grip cover 2714.

FIG. 38B depicts the internals of the trigger mechanism. Grip 2713 alsoincludes a front cover 2714. The front cover 2714 is assembled to thegrip 2713 through fasteners 2724 and orifices 2726 in the grip 2713 andmating parts 2721 in the cover 2714. The mating parts may be molded-innuts, threaded surfaces, or other appropriate joining components.

The internals of the trigger mechanism are largely contained within thegrip 2713. These include a trigger spring 2731, grounded between thetrigger 2715 and a pocket in grip 1713. As noted, spring 2731 determinesthe pull required to activate the trigger. This spring also provides areturn for the trigger to its resting or neutral position after eachpull by the user. Mounted within a channel 2734 in grip 2713 are avertical braking/release bar 2735, vertical driving bar 2737 and adriven horizontal bar 2738. Trigger 2715 also has an internalrectangular bore (not shown) for accommodating driven horizontal bar2738.

Driven bar 2738 in one embodiment has a rectangular cross section, whilethe driving and braking/release bars 2735, 2737 have bores withrectangular cross sections and are mounted around the driven bar via therectangular bores. Bar 2738 has a square cross section in oneembodiment, as do the matching bores in the braking and driving bars.Other configurations may also be used for the bars 2735, 2737 and 2738,and the corresponding bores. Driven bar 2738 includes a pin 2739, whichis connected directly to a bore (not shown) on the rear of the secondplate 2717. Biasing spring 2733 is grounded between the driving bar 2737and braking/release bar 2735, which is somewhat longer than driving bar2737. Biasing spring 2733 maintains compression and separation betweenthe braking and advancing bars. Trigger 2715 is also mounted around thedriven bar 2738 via a rectangular bore in this embodiment. Otherembodiments may include different geometries for driven bar 2738 and thecorresponding bores in the trigger, the driving bar and therelease/braking bar. These shapes may include rounded rectangular, ovateand others.

Compression spring 2712 biases the braking/release bar 2735 to a brakingposition by maintaining contact between the braking/release bar 2735 anddriven bar 2738. Release pin 2736 protrudes above the top of the grip2713 and is used by the operator to release the driven bar from thebraking and driving bars. When a user wishes to return the second plate2717 to a forward position, or to select a position for the secondplate, the user simply presses on pin 2736. Pressing on pin 2736 has theeffect of pushing the release/braking bar 2735 to the rear by overcomingthe compression of spring 2712. Releasing the braking bar 2735 enableseasy manual movement of the driven bar 2738 and thus second plate 2717and the outer sheath of the catheter.

The trigger mechanism works in this manner, although many otherembodiments are also possible, as also discussed in U.S. Pat. No.7,699,297. When the user activates the control mechanism by pulling thetrigger, the driven bar 2738 moves to the rear, to the right in FIGS.38A and 38B, as does the connected second plate 2717. The outer sheathis also connected to the second plate, and as the second plate moves tothe right or rear, the outer sheath does also, thus pulling the outersheath in a proximal direction and exposing more of the prosthesis andthe inner control wire. The distance traveled by the activating bar isdetermined by outer dimensions of the driven bar, the height of the borein driving bar 2737, the distance between the driving bar 2737 and thebraking/release bar 2535, and length of the vertical distance in thebore of trigger 2715. These lengths or distances determine the anglesbetween the various components and thus limit the distance that istraveled by the trigger, the driving bar and the driven bar, on eachpull of the trigger. Thus, each pull of the trigger moves the driven bar2738, the second plate 2717 and the outer sheath of the catheter 2653 apredetermined distance. This makes it straight-forward for the medicalprofessional to deploy the prosthesis. Each pull of the trigger willretract the outer sheath or advance the control wire a known andrepeatable distance.

Returning to FIG. 38A, the outer sheath 2653 is grounded to the secondplate 2717 via connector 2722, which provides both a mechanicalconnection to the control device through second plate 2717 and also afluid connection to irrigation system 2720. The connector 2722 connectsto the irrigation system 2720 through tubing 2723 to a three-way valve2725. The valve may also include other tubing connections 2723 or to oneor more connectors (not shown), and one or more optional caps 2727. Asnoted above, the irrigation system may be used by the physician to flushthe prosthesis and outer sheath with sterile fluid before use, and tocheck for and remove and bubbles in the catheter and in the prosthesis.Such fluid will exit at the far end of the outer sheath 2653 afterconnector 2573 and cap 2575 are removed.

In one embodiment, the control system 2700 includes an internalmechanism that determines the amount of movement of the first or secondplate when the trigger is pulled, and thus when the outer sheath isretracted or in the control wire and prosthesis is advanced. As noted,the amount of force needed for a single trigger actuation may be set byspring 2731. The remaining internal mechanisms, as discussed above, setsthe distance traveled. The catheter is advanced to a point where thecatheter and the prosthesis are in the desired location within thepatient, as determined by the radiopaque methods described above, or byother desirable, reliable method.

The tip of the catheter is advanced through a surgically-created openingin the atrial septum. The tip is thus in the left atrium at the start ofthe deployment process. When the trigger is pulled, the outer sheath isretracted a distance sufficient to remove the outer sheath from aroundthe left atrium legs and flange. In embodiments, this distance is about7 mm. At this point, the left atrium legs are deployed inside of theleft atrium, similar to FIG. 27, step 6000, which shows the left flangelegs deployed from the outer sheath of catheter 111 into the leftatrium. The entire catheter system is then pulled back such that theleft atrium legs contact the septal wall, as seen in FIG. 27, step 6010.At this point, the central portion of the interatrial vent and the rightatrium legs and flange are still retained by the outer sheath. Thecentral portion, still retained, is located in the septal opening. Theright atrium legs, still retained, are located in the right atrium. Asecond pull of the trigger retracts the outer sheath a distance, about 7mm, to remove the outer sheath from around the central portion and theright atrium legs, thus deploying the central portion and also deployingthe right atrium legs in the right atrium.

While 7 mm is a central value, the actual value may vary from about 3 mmto about 11 mm. In other embodiments, other travel ranges may be used.It will also be understood that this distance may vary, due to tolerancestack ups of the several components, including those of the catheter andthe control device.

At this point, the prosthesis has been deployed, and the physician willnormally inspect the deployment by one or more of the non-invasivetechniques described above to insure correct placement. If deployment issatisfactory, the physician may remove the catheter and all components,including the tip, the outer sheath, the control wire, and so forth, andfinally the guide wire used.

During implantation, the physician may use the catheter fluid system todetermine the precise placement of the end of the outer sheath and thusthe prosthesis. After the device has been advanced through the patientto a point near to the desired implantation point, the radiopaquemarkers on the left or right atrium flanges or the catheter may be used,along with fluoroscopy, echosound or other non-invasive means, todetermine the location of the device within the patient. In addition to,or instead of the radiopaque markers, the irrigation system may use aradiopaque solution, such as a barium solution or other radiopaquesolution.

The control device or handle of FIGS. 38A and 38B is merely one exampleof a delivery or deployment device and control device, as discussedherein, for use with a delivery catheter. Other control devices may alsobe used, such as additional examples depicted in FIGS. 39A, 39B-39E and40.

Another embodiment of a control device is depicted in FIGS. 39A and39B-39E. In this embodiment, as seen in FIG. 39A, control device 2790connects to delivery catheter 2788 for delivering a prosthesis. Controldevice 2790 includes a control body 2791 and a control handle 2792. Thecontrol body 2791 is attached or connected to the outer sheath 2784 viaconnector 2797. The moveable control handle 2792 is attached orconnected to an inner control wire 2786 (not visible in FIG. 39A) viaconnector 2799, and as seen in FIG. 39B, connected to the deployableprosthesis 2780. Connector 2798 is a fluid connector for supplying fluidto the inside of catheter 2788 and the inside of outer sheath 2784. Thefluid may be sterile fluid, or may be a sterile radiopaque fluid.Control handle 2792 is equipped with a thumb ring 2794, while thecontrol body 2791 includes two finger rings 2796. Handle 2792 is alsoequipped with a protruding bump or tab 2793, which is sized and designedfor sequential positioning in orifices 2795.

In the sequence, depicted in FIGS. 39B-39E, control body 2791 remainsstationary, as does outer sheath 2784, while the control handle 2792moves progressively to the left, i.e., in a distal direction, in aseries of discrete steps, as shown. As the tab 2793 moves to the left,from the first of the orifices 2795, on the right to the last orifice2801 on the left, the tab is visible in one orifice after another, asshown. At the same time, distal tip 2785 also moves progressively to theleft, distally, to sequentially deploy more and more of prosthesis 2780.In a first view, (FIG. 39B), there is no deployment. In the middle twoviews, (FIG. 39C, 39D) left atrium flange 2787 is first partiallydeployed and then fully deployed. In the final view, (FIG. 39E), bothleft and right atrium flanges 2787, 2789 are deployed. The final viewalso allows a close-up of the delivery catheter details, including tip2785 and non-invasive imaging markers 118 on the tip 2785, just proximalto the tip, and just distal of the deployed prosthesis 2780.

In this embodiment, the control handle 2792 advances control wire 2786and thus the prosthesis 2780 in a sequenced manner that is controlled bythe spacing a, b, c, between the orifices 2795 of the control body 2791.In one embodiment, the distances are 16 mm, 5 mm and 11 mm,respectively. Other embodiments may use other discrete distances. Thesedistances help the medical professional who deploys the prosthesis tomore accurately position the prosthesis within the patient. The deviceand sequence shown in FIGS. 39B-39E uses a stationary outer sheath and amoving inner control wire and prosthesis. It is understood that thehandle 2792 could alternately be attached to the outer sheath, so thatthe tab 2793 begins in the most distal position, as shown in the lastmovement of the sequence, and then the handle and tab move proximally toretract the outer sheath, thus deploying the prosthesis.

In addition, of course, non-invasive imaging is used to position thecatheter outer sheath 2784 and distal tip 2785 to a desired positionwithin the patient, i.e., with the distal top 2785 through an opening inthe atrial septum of the patient. Differences between patients may alsobe studied, and the position of the control handle 2792 may be adjustedslightly for optimal prosthesis placement. As noted in otherembodiments, markers for x-ray or echogenic imaging may be placed on theprosthesis, on the delivery device, or both, to assist in accurateplacement. Using these markers, the medical professional or surgeonimplanting the device may make adjustments to the position of the outersheath, the prosthesis and the relative distances between them. Theprosthesis may then be deployed as desired and the implanting catheter,with its tip, inner control wire, and so forth, retracted from thepatient.

In FIG. 40, another control device 2170 includes a hollow cylindricalbody 2171, with a central channel 2172. There is a series of bores 2173for use with a set pin 2174 to set the position of a front slider 2190with a hollowed-out portion 2191 for retaining an outer sheath or outerportion of the deployment device. The outer sheath is anchored withinslider 2190 and its motion is controlled by a hand actuator 2195 with athumb grip 2197 for use in moving the slider backward or forwards. Theslider 2190 is connected to the hand actuator 2195 via an adapter 2175and pin 2178. Thus, the slider, and the position of the outer sheath maybe retained in place using a bore 2192 in the slider and retaining pin2174, along with the hand actuator 2195.

Adapter 2175 and pin 2178 connect slider 2190, and an attached outersheath, to the hand actuator 2195. Pin 2198, also known as a member, onthe bottom surface of hand actuator 2195, restrains the movement of thehand actuator to the paths molded into the outer surface of the controldevice body 2171. These paths include forward track 2184, intermediatetrack 2182, and rear track 2179. The lengths of the forward and reartracks are thus fixed or predetermined distances. The forward and reartracks 2184, 1289 are generally parallel and are separated byintermediate, transverse track 2182.

The control wire of the catheter is connected to a rear retainer 2180with one or more hollowed-out portions 2183 for securing the controlwire or inner portion of the deployment device. The rear retainer 2180is easily held in place securely and movably by a molded-in retainingnut 2181 and a threaded rod 2177. The handwheel 2176 itself fits snuglyinto the proximal, enlarged portion of the cylindrical body 2171. Thehandwheel may be pinned in position and may rotate in place to allowtranslation of the rear retainer 2180 and thus the inner control wire.The handwheel 2176 and the threaded rod 2177 allow fine adjustments tothe position of the control wire with respect to the position of theouter sheath.

In use, the physician or other medical professional will advance thecatheter using the non-invasive imaging techniques already described.The prosthesis is advanced to the point where the catheter tip is in theleft atrium, while all portions of the prosthesis remain within theouter sheath. The slider 2190 is fixed in a distal position using pin2174, the forward or most distal orifice of the series of orifices 2173,and orifice 2192 of the slider 2190. At this point, the hand actuator isat its most distal position, and pin 2198 is all the way forward, to theright in right track 2184, i.e., the most distal position.

At this point, the left flange is positioned within the patient's leftatrium, still remaining with the outer sheath, and the retainer 2180 islocked in position and not moved further. The outer sheath is thenretracted using the slider 2190 and hand actuator 2195, similar to step6000 in FIG. 27. In one embodiment, the outer sheath is retracted bysliding the hand actuator 2195 straight to the rear and proximally, orto the left in FIG. 40. This movement is allowed by the rearwardmovement of member or pin 2198 in right track 2184. This movement is afixed distance, until the pin strikes the rear of the long portion 2184and the start of transverse portion 2182 of the molded-in paths and cango no further. The length of the long portion 2184 is fixed when thelong portion is molded or machined into hollow cylindrical body 2171.The distance is that needed to deploy the left flange of the interatrialpressure vent or prosthesis. The distance may also be that needed todeploy the left flange and the central or valve portion. In oneembodiment, this distance is about 7 mm. In other embodiments, thedistance may be 5 mm, 6 mm, 8 mm, 9 mm or other desired distance.

After the desired portion has been deployed, the physician may usefluoroscopy or echosound to determine the exact position of theprosthesis with the patient before proceeding. If an adjustment isneeded, the prosthesis can readily be retracted into the outer sheathfor removal or redeployment at this stage, as will be seen in some ofthe improved designs for retrieval and redeployment described below.

If continuation is indicated, the surgeon or medical professional willthen prepare to deploy the remainder of the interatrial pressure vent orprosthesis. The first step is to rotate the hand actuator 2195 a fewdegrees to the right so that pin 2198 is now in the other long track2179. The transverse portion 2182 is only about twice as wide as pin2198. Rotation of the hand actuator thus does not cause the prosthesiswithin the patient's heart to translate proximally or distally. Thesurgeon then moves the hand actuator in a proximal direction, to theleft in FIG. 40, further retracting the outer sheath and deploying theright atrium flange into the right atrium of the patient's heart. Thelength of track 2179 is also a fixed distance, the distance fixed whenthe track is molded into the hollow cylindrical body 2171. In oneembodiment, the distance is 8 mm, a little longer than the length oftrack 2184. In other embodiments, the distance may vary, as noted above.The distances, or the length of the tracks, may be tailored to fit thepatient's anatomy, for example, by determining ahead of time the widthof the patient's septum or the dimensions of the patient's heart.

In another embodiment, not shown, the two tracks of predetermined lengthmay be a single length with a pin or other obstacle inserted at adesired point along the length of the track. The pin will preventfurther movement of pin 2198 in a proximal direction and will stop themovement of the hand actuator 2195 after it has moved a fixed orpredetermined distance, e.g., 7 mm. After the pin is removed, thesurgeon or other medical professional may continue to move the handactuator in a proximal direction along the remainder of thepredetermined or fixed length of the track.

As described above there are situations where the deployment may not besatisfactory for any of a number of reasons, and the prosthesis may beremoved from the patient. This situation may become apparent before theprocedure has been completed. In some cases, the need for removal maybecome apparent while the guidewire and/or catheter delivery system withwhich the procedure was begun is still in place, such, for example, theembodiments described in connection with FIG. 19A. In other cases, itmay be necessary to introduce a guidewire to begin a removal procedure,while in other cases a guidewire is not used. If the prosthesis has notbeen fully deployed, removal may be accomplished by retracting thecontrol wire attached to the prosthesis, or by advancing the outersheath over the prosthesis. Removal is then accomplished by merelywithdrawing the outer sheath and all its components. Once the prosthesishas been deployed, different techniques may be needed, as depictedabove, and now below. The method of retrieval will depend on thecharacteristics of the device. Some methods of retrieval have alreadybeen discussed above. Below are some other methods.

Retrieval of the fully deployed prosthesis is depicted in FIGS. 41 and42, while the tools used for retrieval are depicted in FIGS. 41, 42 and43. The retrieval device 2750 is advanced to the desired location withinthe patient along a guidewire 2751. Components of the retrieval device2750 include an outer sheath 2752, an inner sheath 2753 and a grasper2755, such as the three-prong grasper depicted in FIG. 41. In oneembodiment, the outer sheath has an outer diameter of about 21 Fr (about7 mm) while the inner diameter is about 6.7 mm. In the figure, thegrasper 2755 has caught the prosthesis 2757 with one of the three prongs2755 a and its protruding hook or tab 2755 b. As noted, the tab 2755 bmay be useful for insertion into an orifice of a prosthesis leg orstrut, as seen in FIG. 2A, for retrieval of the prosthesis. In FIG. 2A,legs 103 x of the flanges meet at a juncture, an apex or an end of twoof the legs. Each flange of the prosthesis includes two or more legs,usually in pairs, each pair also forming an apex where the legs meet.

It will be recognized that one or more components of the retrievaldevice may include radiopaque components or markers for bettervisibility by non-invasive techniques, such as fluoroscopy, echo-sound,and so forth. In one embodiment, one or more of the prongs of thegrasper may be made of a radiopaque metal or material, such as themetals themselves or alloys of gold, platinum, palladium, tungsten andtantalum. In another embodiment, the prongs of may include one or moremarkers, e.g., a small dot or implant of a radiopaque material orechogenic material that will be easily detected by x-ray, fluoroscopy,echosound or other suitable non-invasive imaging technique.

In use, the retrieval device is advanced to the desired location withinthe patient, using non-invasive techniques and radiomarkers, echogenicmarkers, or other indicators on the device. The user has three controlsto manipulate the device, in addition to advancing and retracting theentire device 2750, e.g., while the internal portions are containedwithin the outer sheath 2752. The inner sheath 2753 has a control wire(not shown) as does the grasper 2755 (control wire not shown). Theretrieval basket 2758, depicted in FIGS. 42 and 43, also is advanced andretracted using its control wire (not shown), as will be understood bythose with skill in minimally-invasive surgery arts. The grasper 2755,as the innermost component and nearest the guide wire, may have amicro-rail, i.e., a lumen or longitudinal cavity, to follow preciselythe path of the guide wire. In other embodiments, it is possible toassemble the retriever so that an inner sheath is not used. For example,if the basket is assembled proximally from the grasper, and the graspersufficiently distal from the basket, an inner sheath and its controlwire may not be needed.

The user advances the device 2750 and outer sheath 2752 near the desiredpoint and verifies the location. The user may then advance the innersheath 2753 out from the outer sheath 2752. The user may then advancethe grasper 2755 from the inner sheath and maneuver the grasper and theinner sheath, or the grasper or the sheath separately as desired, tograsp the prosthesis 2757 with the prongs of the grasper. There is noseparate closing control for the grasper. The user simply maneuvers thegrasper in such a manner that when the grasper is retracted, the prongsapproach each other in a manner to grasp and retrieve the prosthesis.The control wire or control handle for the grasper in one embodiment hasa locking feature that allows the surgeon to close the grasper and notbe concerned about further manipulation of the grasper, except forwithdrawal. In one embodiment, the grasper is a three-pronged Hobbsforceps, available from Hobbs Medical, Stamford Springs, Conn., USA. Inanother embodiment, the grasper or the retrieval device may also have afluid channel for irrigating the retrieval site, much as the deploymentcatheter has a fluid channel.

Other graspers or retrievers may be used instead, such as those withfour prongs, or even other retrieval devices, such as a single prong ortab. The single tab or prong may be in the form of a short cylinder,suitable for insertion in an orifice of the struts or legs of a flangedatrial septum implantable device, as shown in FIGS. 2A and 7B. The usermaneuvers the grasper or tool so that the implantable device is hookedby one or more of the orifices, and then uses this connection toretrieve the implantable device.

In other embodiments, the implanted device may have one or more legs ofthe right atrium flange longer than most legs of the flange, making iteasier to grasp one or more of the legs or struts, as shown above inFIGS. 7B and 7C. In these embodiments, the grasper may more easilyapproach the implanted device and grasp it, whether a multi-pronggrasper is used, or whether a single tab or prong is used to grasp thelonger leg. In other embodiments, the implanted device may have a flangemore suited for retrieval, such as the conical flanges depicted in FIGS.22 and 23. In these embodiments, it is relatively easy for a user tograsp the conical apex 450 for retrieving the implant via a grasper, asdiscussed above. Retrieval is more user-friendly also, since the shapeof the implant lends itself to being pulled in the proximal direction,i.e., towards the outside of the body of the patient.

The inner sheath and the grasper are then retracted, as shown in FIG.42, and the basket 2758 is deployed by advancing its control wire (notshown). Basket 2758 may be made from metal mesh, such as Nitinol orother medically-acceptable, shape-memory material. Nitinol is a goodchoice because it can be trained to assume the desired basket form as itdeploys from the outer sheath. There may also be a barrier layer 2759 tohelp prevent any undesired piercings by wires or components of theprosthesis. The barrier layer may be made of a suitablemedically-acceptable cloth, such as polyester (Dacron®, for example), orother material. Once the prosthesis is grasped and the basket deployed,the grasper 2755 and the prosthesis may be retracted into the basket byadvancing the basket or retracting the grasper and prosthesis, or both.The basket, grasper and prosthesis are all withdrawn into the outersheath, which may then be safely removed from the patient with theretrieved prosthesis.

As noted, basket 2858 may be made from metal mesh, such as a mesh madefrom Nitinol or other wires. In one embodiment, Nitinol wires may be0.003 inches in diameter (about 0.08 mm in diameter); in anotherembodiment, the wires may be 0.020 inches in diameter (about 0.51 mm indiameter). Other embodiments may use flat wires or ovate-shaped wires.Basket 2759 is made from a single layer of Nitinol mesh. Otherembodiments, such as the one depicted in FIG. 43, may use a basket 2760having two layers, i.e., a basket including an inner layer 2761 foldedover to form a second, outer layer 2762. The two-layer basket may bebetter at preventing objects within the basket from protruding outsidethe basket.

Retrieval Devices with Dilators

It is clear that the outer sheath of a retrieval device, and allcomponents, should be as small and as thin as possible for patientcomfort. Accordingly, in one embodiment, the outer sheath has an outerdiameter of about 18-20 Fr. In one embodiment, the deployed basket has alargest outer diameter of about 20 mm, which is quite large compared toa 20 Fr outer catheter outer diameter. In other embodiments, the sizesmay be larger or smaller, as needed. It is clear from inspection of thebasket in FIGS. 42 and 43 that the space used to accommodate devices forretrieving the prosthesis will be somewhat greater than the spacetypically used to deploy the prosthesis.

In order to ease the transition, a retrieval device may use a dilator onits distal end. While the tip is nominally termed a dilator, it does notexpand, rather its purpose is to maintain the dimension of its widestportion while the forceps or other device within the sheath is deployedbehind the tip. Two embodiments are depicted in FIGS. 44 and 45. In FIG.44, retrieval device 2765 includes an outer sheath 2766 and device tip2767. The device is introduced into the patient via a guidewire 2771.Retrieval device 2765 includes a grasper or forceps 2768, a jacket orouter covering 2769, as discussed above, and a braided capture sleeve2770, such as a capture sleeve made from Nitinol mesh. Retrieval device2765 also includes X-ray or echogenic markers 2774 in useful locations,such as at the distal end of the outer sheath 2766 or the dilator 2767.

In use, the device tip is deployed when the user pushes the forceps 2768distally, or withdraws the outer sheath 2766 in a proximal direction.The device tip is constrained to move axially along the guidewire 2771,and its location will thus remain in the control of the medicalprofessional deploying or retrieving the prosthesis.

The embodiment of FIG. 44 features a device tip with a rather longtransition section. When the user has advanced the retrieval device tothe desired location within the patient, the sheath is withdrawn in aproximal direction, or the forceps is advanced in a distal direction todeploy the forceps and the basket. Because the device tip has a verygradual transition, the movement and the disruption to the patient areminimal. In this embodiment, the angle A of the device tip may rangefrom about 10 degrees to about 30 degrees. Other angles may be used. Thelength of the transition section may vary from about 15 mm to about 25mm Other lengths may be used.

Another embodiment is depicted in FIG. 45. In this embodiment, theretrieval device 2775 also has an outer sheath 2776 and a separabledevice tip 2777. As shown in this view, the angle of the device tip ismuch greater than the previous embodiment, while the length of thedevice tip is much shorter. Retrieval device 2775 includes an innersheath 2781 and a balloon 2782 and an inflation/deflation lumen 2783.Retrieval device 2775 also includes X-ray or echogenic markers 2779 inuseful locations, such as at the distal end of the outer sheath 2776 orthe dilator 2777. The length of the transition section may vary fromabout 5 mm to about 120 mm. Other lengths may be used.

In this embodiment, the retrieval device is used with the device tip andthe internal balloon that is inflated to create a space for theretrieval device. In this embodiment, the retrieval device 2775 does notinclude a retrieval forceps at the outset. After the device tip isdeployed and the balloon is expanded to create a space, the balloon isdeflated and retracted and a retrieval forceps and basket are exchangedalong the guidewire for the balloon and the inflation equipment. Theballoon may be expanded by inflating the balloon to a pressure from 6atm to 20 atm.

Some Designs for Retrievability and Redeployability

FIGS. 46-49 depict additional embodiments of interatrial implantableprostheses which have been designed for easier retrieval and also forredeployment once they have been retrieved. A first improved embodiment100 a is depicted in FIGS. 46A-46B. The drawings depict several views ofbody element 100 a, showing how the ends of flange segments 102 a-102 h,103 a-103 h are rounded at their distal ends 115 and 116 to reducestress concentrations against the interatrial septum after placement.These distal ends, or apices where the strut legs intersect, includebores 109 a, 109 b, 110 a, 100 b into which radiopaque or echogenicmarkers 118 a, 118 b and 119 a, 119 b can be positioned. Using thesemarkers, the device may more easily be visualized using radiographicimaging equipment such as with x-ray, fluoroscopy, magnetic resonance,ultrasound or other imaging techniques. Markers as disclosed herein maybe applied to the ends of any segments, not just those with holes oreyelets therein. Radiopaque or echogenic markers 118 a, 118 b, 119 a,119 b can be swaged, riveted, adhered, or otherwise placed and securedinto the bores and dimensioned to be flush with the contours of thesegments.

The retrieval legs described herein may be made from nitinol wire,stainless steel wire (such as grades 304, 304L, 316 and 316L, amongothers), nylon sutures (e.g., polyamide), polypropylene sutures (e.g.,Prolene®), or any other material that is medically acceptable andresistant to stretching. Materials that assume a known shape aredesirable, as are materials that are visible under echographic or x-rayimaging conditions. The legs may thus take on a filamentary, thread,suture or wire shape, and may comprise a single thread or wire, or morethan one suture, filament or wire. Wires made from nitinol or othermetals may have a thickness from about 0.004 to 0.025 inches (about 0.11to 0.64 mm). Sutures may range from about 8-0 to 7 (U.S.P.designations), i.e., from about 18 to 40 AWG, or even a little thinnerthan 40 gauge. The diameters of such sutures will range from about 0.04mm to about 0.8 mm, and may apply to collagenous materials, syntheticabsorbable materials, and synthetic non-absorbable materials.

FIG. 46A depicts several retrieval legs 135 joined to a central nub 137.The retrieval legs may be made of nitinol wires or of sutures and may beconnected to the bores 109 of right atrium flange legs 102 a-h, or beformed integrally with the right atrium flange legs, and extend to acentral juncture or nub 137. Portions of the sutures or wires may bemade from radiopaque materials or MR-visible materials so that the nub137 is visible using non-invasive imaging techniques. At a juncture, theretrieval legs may be joined into a short tube 175 and crimped into tube175. A single suture or wire loop 177, or more than one loop, may thenextend above the crimp for joining to the inner catheter control wire,or for grasping by a retrieval device. A typical crimp tube is visibleunder x-ray or echographic (sound) imaging. Thus, the tube may bestainless steel or radiopaque plastic. One embodiment of the tube has a0.035 inch i.d. (0.90 mm), 0.008 in (about 0.2 mm) wall thickness, andabout a 0.050 inch (1.3 mm) o.d. Other embodiments may be used.

Retrieval loop 177 may be radiopaque or echograpically visible, or mayinclude one or more threads that are radiopaque or echo-visible, such asa gold or platinum thread. The retrieval legs of this design do notinterfere with the function of the prosthesis but do extend a shortdistance proximally, as shown in FIG. 46B. Thus, a filter, such as athrombus filter, is described. In addition, the flow control elementsdescribed above may be used in the central portion of the prosthesis.These include the bivalve of FIG. 26, or a tri-lobal valve, or otherembodiments, such as those discussed above with respect to FIGS.29A-29C.

The prosthesis of FIGS. 46A-46B may be deployed from a catheter, asdescribed above, and is retrieved in a similar manner, described below.The retrieval device secures suture or wire 177 from the central tube orcrimp 175 with an appropriate end-effector, hook or grasper on its innercontrol wire. The inner wire of the retrieval device is then withdrawnproximally, drawing the sutures or wires into a catheter, collapsing theright atrium flange, and then drawing the remainder of the prosthesisinto the catheter. The device may then be withdrawn from the patient, ormay also be redeployed, perhaps in a better position.

A second design specifically for retrievability is depicted in FIGS.47A-47B. Prosthesis 141 is similar to prosthesis 100 a of FIGS. 46A-46B.FIG. 47A is a top view, depicting prosthesis 141 with retrieval wires orsutures 143 connected to the apices 102 a-h of the right atrium flange.In this embodiment, there are two central nubs or points 145, each forabout 180 degrees of the flange. The retrieval wires 143 are tiedtogether to form a nub 145 on each side of the right atrium flange. Asseen in FIG. 47B, the nubs 145 are then joined with a crimp tube 175,with a loop 147 of one or more retrieval wires or sutures joining thetwo crimp tubes 175 and sides of the prosthesis for removal. Theretrieval wires or sutures, and the nubs, may be made from the materialsdescribed above. As depicted in FIG. 47B, the wires or sutures avoid thecentral area of the prosthesis when deployed from catheter 173 and thusdo not interfere with the functioning or deployment of the valve. Thewires or sutures are available to assist in withdrawal and removal orredeployment of the prosthesis if needed. Retrieval loop 147 may beradiopaque or echographically visible, or may include one or morethreads that are radiopaque or echo-visible, such as a gold or platinumthread.

A third embodiment of a design for retrieval is depicted in FIGS. 48Aand 48B. In this embodiment, prosthesis 151 is very similar toprosthesis 141 above, including retrieval sutures or wires 153 frombores 109 of the right atrium flange apices 102 a-h, to a centralannular retrieval suture or wire 157. Each retrieval suture or wire 153is joined to the central retrieval thread 157 at a juncture 155. Thejunctures may simply be suture tie-offs; alternatively, the juncturescould be orifices in central wire 157 for joining retrieval sutures orwires 153. In some embodiments, an additional retrieval suture or wire147, suitable for non-invasive imaging, may be tied to the centralthread at least at one point for grasping by a retrieval device.

A fourth embodiment of a prosthesis 161 designed for retrieval andredeployment is depicted in FIG. 49. Prosthesis 161 is similar toprosthesis 100 a, described above. In the fourth embodiment, there is aretrieval wire or suture 163 secured to each apex 102 a-h of the rightatrium flange and there is a retrieval wire or suture 167 secured toeach apex 103 a-h of the left atrium flange. The right atrium flangeretrieval wires or sutures are joined to a central point or nub 165 andsecured to an inner control wire 171 b of a catheter 173. Central nub165 may be a crimp tube and retrieval suture or wire, as describedabove. The left atrium flange retrieval wires or sutures are also joinedto a central nub 169 and secured to an inner control wire 171 a. Centralnub 169 may be a crimp tube and retrieval suture or wire, as describedabove. To deploy the prosthesis 161, the medical professional positionsthe prosthesis in the correct position within the patient and thenreleases the left atrium flange, disengaging the inner control wire fromnub 169, and also releases the right atrium flange, disengaging theinner control wire from nub 165.

If retrieval is desired, the grasper or retrieval device grasps orengages both nubs 165, 169, preferably separately, with inner controlwires 171 a, 171 b, or with graspers attached to them, to collapse therespective flange and withdraw the prosthesis, as described below. Inone embodiment, left atrium flange legs 103 a-h have a greater radius Rat their root and may even approach the septum wall at an obtuse angle,i.e., as shown in FIG. 49. This larger radius will make it easier tocollapse the legs and struts of the flange. Once the prosthesis iswithdrawn, it may be redeployed to a better position within the patient.Prosthesis 161 is capable of having both its left and right atriumflanges collapsed. If separate control wires are used, one for eachflange, the flanges may be collapsed separately in time, thus requiringless force to withdraw.

Stents for Providing Coronary Sinus Pressure Relief

Per the discussion on heart failure, and consistent with the presentinvention, it may be beneficial for some patients to relieve pressure inthe left atrium. One way to accomplish this is to provide communicationbetween the left atrium and the coronary sinus. The coronary sinus andits tributaries receive approximately eighty-five percent of coronaryvenous blood. The coronary sinus empties into the posterior of the rightatrium, anterior and inferior to the fossa ovalis. A tributary of thecoronary sinus is called the great cardiac vein, which courses parallelto the majority of the posterior mitral valve annulus, and is superiorto the posterior mitral valve annulus.

Thus, by providing communication between the left atrium and thecoronary sinus, inappropriate pressures in the left atrium can beaverted, with the blood diverted to the most appropriate blood vesselpossible, the coronary sinus. In cases of mitral valve failure ordisease, it is possible that providing this communication could allowthe patient to put off or forgo mitral valve repair. This could provideadditional quality of life to the patient, while avoiding surgery thatis more involved and more delicate.

Embodiments of the stent described herein may be placed viaminimally-invasive surgery, such as through endoscopic or percutaneous(vascular access) routes, or by traditional surgical methods. Minimallyinvasive procedures are more easily tolerated by the patients, who mayalso recover much more quickly from the procedure. In embodiments wherethe device is implanted into the atrial wall via a minimally invasiveprocedure, a catheter may be used, as shown generally in FIG. 50. Acatheter, such as an introducer catheter is introduced through a jugularvein or a subclavian vein, through the superior vena cava (SVC), alongthe path of arrows A, and into the coronary sinus CS of the heart H. Itis also possible to place the catheter via a femoral vein, through theinferior vena cava (IVC), along the path of arrows B, and into thecoronary sinus.

As is well known to those with skill in surgical arts, it is useful tofirst define the pathway via a guidewire, such as a 0.035 inch diameter(about 0.9 mm) guidewire or 0.038 inch dia. (about 1 mm) guidewire.Guidewires of other diameters may be used as needed or desired. Thecatheters may be maneuvered to their locations by carefully followingthe appropriate guidewire. It is also well known to those with skill insurgical arts that other pathways for the catheter may be used, such asthrough the pulmonary veins, or even through arterial pathways. Ifpatient anatomy suffices, however, the easier method is to go throughthe route of the SVC as discussed above.

FIG. 51 depicts one method of deploying the stents described herein. InFIG. 51, a guide wire 10 is introduced through the jugular vein (notshown), through the superior vena cava and into the coronary sinus. Oncethe wire guide provides a path, an introducer sheath 12 may be routeddown the guide wire and into position in the coronary sinus. Theintroducer sheath or introducer catheter is used to provide vascularaccess. The introducer sheath may be a 16 F or less hemostasisintroducer sheath. Alternatively, the subclavian vein may be used. Inone embodiment, introducer sheath 12 may be about 30 cm long. Theguidewire may be somewhat longer for ease of use. In some embodiments,the introducer catheter may also function only as a dilator and anassistant for preparing an opening in the wall of the left atrium. Inthese embodiments, a separate placement catheter will be used. In otherembodiments, the introducer catheter may be used as the placementcatheter also.

Since the coronary sinus is largely contiguous with the left atrium,there are a variety of possible acceptable placements for the stent. Thesite selected for placement of the stent, may be made in an area wherethe tissue of the particular patient is less thick or less dense, asdetermined beforehand by non-invasive diagnostic means, such as a CTscan or radiographic technique, such as fluoroscopy or intravascularcoronary echo (IVUS).

In FIG. 52, a bending catheter 16 is depicted, guide wire 10 is still inplace but is not shown for clarity. In one embodiment, bending catheter16 may be about 145 cm long. A closer look at the introducer catheter 12and the bending catheter 16 is depicted in FIG. 53. The introducercatheter 12, equipped with a peripheral opening 13 and at least onemarker 14 for radiographic or echogenic location, is shown within thecoronary sinus. As noted, the wire guide 10 is still in place. In oneembodiment, bending catheter 16 is about 145 cm long and has a veryflexible or floppy tip 18 for precisely positioning the catheter. In oneembodiment, the tip 18 is capable of a 90° bend so that the medicalprofessional has very close control of its location and can easily usethe catheter in the desired location. Bending catheter 16 is alsoequipped with one or more echogenic or radiographic markers 14 near thetip so its location may be discerned by non-invasive means, such asfluoroscopy or ultrasound techniques. Catheters with very flexible,e.g., floppy 90° distal tips, are available from Baylis Medical Company,Inc., Montreal, Canada.

As further shown in FIG. 54, once the bending catheter 16 and veryflexible tip 18 are in the proper position, an RF wire 19 will be placedinto position through catheter 16 and used to ablate the tissue and topenetrate the wall between the left atrium and the coronary sinus, whichis relatively delicate tissue. Care should be taken, however, thattissue remains integral with the wall and that no loose tissue iscreated when the opening is made.

For example, bipolar or monopolar radio-frequency (RF) energy may beapplied to the desired area to ablate or vaporize tissues in the area toform an opening. Several techniques in this area of described in acopending provisional patent application assigned to the assignee of thepresent application and entitled “Interatrial Pressure Relief Shunt,”and filed on Feb. 10, 2011, U.S. Prov. Pat. Appl. 61/441,546, thecontents of which are hereby incorporated entirely by reference andrelied upon. Additional precautions may be taken in certain of thesetechniques, such as providing a grounding pad for the patient at leastwhen using monopolar electrical equipment.

Piezoelectric ultrasound techniques and piezoelectric ultrasound sensorsor sensor arrays in the desired abrading area, also discussed in theabove-mentioned patent document, may instead be used. Typically, DCequipment is used for RF techniques and equipment while AC equipment isused for ultrasound or piezoelectric equipment. The area in theimmediate vicinity where ablating is to take place may be protected byheat transfer equipment. For example, cooling coils may be delivered bysuitable catheters and placed in the area, such as in an annular ringsurrounding the electrodes or sensors that deliver the ablating energy.Cooling fluids, such as saline, may be pumped through the cooling coilsto counteract the very hot temperatures generated by the ablatingdevices. Ablative equipment is available, for example, from BaylisMedical Company, Inc., Montreal, Canada.

In one embodiment, the opening made in the atrial wall by ablation maythen be enlarged. The RF wire 19 with its flexible tip may be removedthrough sheath 16 and a balloon catheter 20, inserted, through sheath 16as shown in FIG. 55. Balloon catheter 20 may also be equipped withmarkers 14. In this technique, balloon catheter 20 with tip 22 and witha balloon 24 is guided to the opening and the balloon is inserted intothe opening between the coronary sinus and the left atrium. Usinginflation lumen 26, the balloon is inflated and the opening enlarged tothe desired diameter. When the opening has been made, the balloon may bedeflated through deflation lumen 28 and then removed through the sheath16. Alternatively, any suitable dilator may be used, such as a Mullins™dilator with a needle or cutting edge or a conical distal tip of adilator catheter. The method employed must be very reliable and verycontrollable by the medical professional in all stages of itsdeployment. The size of the opening desired may range up to about 8 mm,although smaller openings may also be suitable.

Once the opening is made between the left atrium and the coronary sinus,a deployment catheter 30 is used, as depicted in FIG. 56. Similardepictions are seen in FIGS. 8-11 above, in which the prosthesis is in acompact or folded state prior to deployment. The deployment catheter 30may be used with a guide wire 10 only or it may be used with a sheathcatheter 12, as seen above. In the figures that follow, a sheathcatheter is not shown, for simplicity, but it may be used for ease ofinsertion and then withdrawn before deployment of the stent. Thedeployment catheter 30 includes an outer sheath 32 and an inner controlwire 34. Outer sheath 32 may also include one or more radiographic orechogenic markers 36 so the sheath may be easily seen by non-invasivetechniques and its location adjusted as need for proper placement.

Deployment catheter 30 also includes a stent 40 folded up within thecatheter. As detailed below, stent 40 may be in generally in a shape ofa T, with a longer portion and a shorter perpendicular section. Thelonger portion is intended for implantation in the coronary sinus, withthe perpendicular portion extending into through atrium wall into theleft atrium. The stent should extend through the atrium wall, but theextension into the left atrium should be minimal, for example, only 3-4mm. This distance is believed to insure secure implantation withoutextending so far as to interfere with movement of the left atrium duringnormal heart operation.

Stent 40 is deployed using control wire 34, which extends backwardsthrough catheter 30 to a control device or handle (not shown) accessibleto a medical professional guiding the catheter. As is well known tothose with skill in the art, the catheter is deployed by holding thecontrol wire in place while gently withdrawing the outer sheath 32. Asthe sheath is withdrawn, the stent expands and deploys in place in thecoronary sinus. As is also well known, stent 40 is prepared frommedically acceptable prosthesis materials, such as Nitinol, stainlesssteel, MP35 or other materials. Nitinol or other shape-memory alloysallow manufacturers to prepare stents and train them to assume thedesired shape once they are returned to body temperature and aredeployed in the body. When freed of the restraints of the confiningcatheter, the stent will expand and assume the shape for which it wastrained.

Stent 40 is depicted in its undeployed state in FIG. 56 and in itsdeployed state in FIG. 57. The deployed stent is in a general form of atube, with longer portions 41, 42 intended for implantation in thecoronary sinus and a shorter portion 43, intended to be perpendicular tolonger portions 41, 42 and for extension through the orifice made in thewall of the left atrium. In the deployed state, the shorter top portion43 is intended to protrude through the orifice. In the closer view ofFIG. 57, it is seen that both portions of the stent has the appearanceof about eight struts 44 joined at apices 45, as also shown in greaterdetail above in FIG. 2A. In some embodiments, the stents are not made ofdiscrete struts but rather are laser cut or water-jet cut from a thin,solid tube of Nitinol or other desired material. Thus, the stents maybetter be described as a network, or mesh, of struts and intersectionsof struts. In one embodiment, at least the shorter portion 43, and alsothe longer portions 41, 42 include one or more markers 46 made of aradiopaque or echogenic material. In the closer view of FIG. 2A, notethat the outer portions are smoothly rounded to avoid any trauma to theheart tissue, for example, with a radius of curvature greater than 0.03inches (about 0.8 mm).

The stent thus implanted should be capable of two important tasks. Thestent should be sized so that the longer part, portions 41, 42 remain inplace within the coronary sinus without movement. Accordingly, thediameter of these portions should be in the range of about 8-13 mm,perhaps in the range of 8-11 mm, because the posterior portion of thecoronary sinus, in the desired location, is a little smaller than theanterior portion. With the longer portion of the stent fixed in place,the shorter portion, or crown portion 43, will also remain in place.

Once placed, the crown also will not move and will be in a position tokeep the orifice open between the left atrium and the coronary sinus.Accordingly, it should not be necessary for the upper portion to exertmuch force on the opening, and it will be desirable for this portion tobe flexible and atraumatic rather than stiff. The coronary sinus is verysensitive to abrasion and the stent portions that reside in the coronarysinus need to be atraumatic while the LA legs need to conform to thecurvage or the radius of the opening into the left atrium chamber. Atthe same time the transverse or crown portion of the stent needs to bestrong enough to keep the freshly made opening between the coronarysinus and the left atrium from closing; this would defeat the purpose ofthe prosthesis. In other embodiments, described below, the upper portionmay form a flange, with longer or shorter extensions along thelongitudinal direction of the stent, as shown in FIGS. 58 and 59.

In FIG. 58, stent 50 includes a top portion or flange 51 with about 4protruding triangular struts 53. The radius of curvature is relativelytight, from about 5 mm to 15 mm, so that the flange is not held tightlyby the atrial wall in the vicinity of the flange. The flange in thisembodiment extends about 2-4 mm in a direction parallel to the coronarysinus. In FIG. 59, stent 56 includes a top portion or flange 57 withabout 6 (not all are shown) protruding struts 58. The radius ofcurvature 59 here is somewhat looser, from about 10 mm to about 40 mm.In one embodiment, the flange extends only about 1-2 mm in a directionparallel to the coronary sinus. Like the annular flange described inconnection with intra-atrial stents/devices above, the flange 51 may beannular and comprise a plurality of flange segments in all the sameconfigurations as mentioned above in connection with the intra-atrialstent, including varying flexibility of the flange or flange segments.For example, the flange and/or flange segments may be more flexible thanthe transverse portion of the stent to achieve the atraumatic contactdiscussed in the preceding paragraph.

One aspect of the stents for enabling communication between the leftatrium and the coronary sinus is that it may be desirable to have onlyone-way communication. One embodiment of the stent is designed to allowpressure relief of the left atrium by providing an outlet to thecoronary sinus without allowing retrograde flow. The coronary sinusdirects blood flow from several veins, such as the small, middle, greatand oblique cardiac veins, the left marginal vein and the left posteriorventricular vein. It is not desirable, however, to allow flow from thecoronary sinus into the left atrium. The stent may thus be restricted toone-way flow by providing the stent with a flow control element of thetype disclosed elsewhere herein.

FIGS. 60 and 61 depict two embodiments of a stent limited to one waycommunication by a restricting valve. In FIG. 60, stent 60 includes atop portion 61 intended for deployment above the wall between the leftatrium and the coronary sinus. Stent 60 also includes a transverseportion 67 intended for deployment within the coronary sinus asdescribed above. Top portion 61 in this embodiment includes a multi-partflap valve 63 secured to the top portion 62 of tower 61 with sutures 64.While the flap valve 63 in this embodiment has two portions a bi-valve,that meet roughly along a diameter of the top portion, other embodimentsmay have three or more portions, again, meeting in the middle. It isalso possible to have a single flap, tethered perhaps along one side byabout 30-45 degrees of the circumference. This embodiment also includesone or more stops 65 to prevent the valve from opening in the otherdirection and allowing blood to flow from the coronary sinus into theleft atrium. The flow control element could also be a ball and socketvalve, a duckbill valve, a butterfly valve, or any other valve componentknown to those skilled in the art or as those disclosed in thecommonly-owned application mentioned above.

As is well known to those with skill in cardiac arts, the valve or flapmay be made of mammalian pericardium, such as bovine pericardial tissue,or from ovine or porcine pericardial tissue. Other suitable tissue mayalso be used. In one embodiment, the tissue is about 0.5 to about 1 mmthick. Other thicknesses may be used. The valve and the flaps aredesigned so that blood will flow through the one-way valve when thepressure differential reaches about 5-10 mm Hg. Any of thevalves/materials disclosed above in connection with intra-atrial stentmay also be used.

FIG. 61 depicts another embodiment of a one-way valve useful in thestents disclosed herein. In this exploded view, valve 70 is formedwithin the top portion 71 of a coronary sinus pressure relieving stent.The valve includes a plate 75 with multiple perforations 76. Whileperforations 76 are shown as slots, they may be made of any suitableshape. The plate itself made may be made of any material suitable for invivo contact with blood, including inert polymers such as polycarbonateor polysulfone, or metals such as stainless steels, MP35N or Nitinol. Asshown, perforated plate 75 is adjacent the distal end of the stent topportion 71. On the opposite side of the perforated plate 75 is a valveelement 73 with flaps 74. In one embodiment, flaps 74 are slightlylarger that the gaps beneath the flaps, enabling the flaps to sealtightly if for some reason the pressure in the coronary sinus exceedsthe pressure in the left atrium, on the far side of the stent.

During normal operation, when the pressure in the left atrium exceedsthe pressure in the coronary sinus, blood will tend to flow from theleft atrium through the stent, and in particular at the outset, throughthe top portion 70. Blood will flow through the perforated plate 75 andsince the flaps 74 are free to flap downward, in the embodiment of FIG.61, the blood will flow through valve element 73 and on into thecoronary sinus. However, the flaps 74 are not free to flow in theopposite direction, toward the left atrium, because their movement isprevented by the perforated plate 75. Other embodiments of check valvesor one-way valves may also be used.

Other embodiments of stents for relieving pressure may have otherconfigurations. For example, FIG. 62A depicts a T-tube stent in abefore-deployment configuration. Stent 80 includes a longer portion 81in a general shape of a cylinder for placement in a coronary sinus of apatient. The stent is constructed of short struts 84 and apices 86joining the struts, or as mentioned above, an interconnecting network ofstruts and joining areas. A shorter portion, tower 82 is folded withinthe longer portion 81. Upon deployment of the stent within a patient,the longer portion will expand if the stent has been trained to do sowhen the austenitic transition occurs upon warming to body temperature.The tower portion 82 may then be deployed from its retracted positionwithin the longer portion to its deployed position, as shown in FIG.62B.

The tower will assume its intended shape as it is deployed and as itwarms to body temperature. The tower includes a wider portion, i.e., aportion with a larger diameter that will reside within the left atrium.The tower also includes a narrower portion 83 having a diameter aboutthe diameter of the opening which was prepared for the stent. Towerportion 82 may be pushed into place, for example, by a balloon catheterif it fails to deploy properly by the “memory metal” effect. While theprincipal portion of the stent is constructed of struts and apices, inthis embodiment, the tower may be made from many more flexible, thinnerwires 88 for greater ease of deployment. In one embodiment, the wiresare 0.003 in (0.08 mm) diameter and are thus very flexible. The wiresform a porous closed “net” whose openings allow blood to flow from theleft atrium to the coronary sinus.

While the invention has been disclosed in connection with the preferredembodiments shown and described in detail, various modifications andimprovements thereon will become readily apparent to those skilled inthe art. Accordingly, the spirit and scope of the present invention isnot to be limited by the foregoing examples, but is to be understood inthe broadest sense allowable by law.

The use of the terms “a” and “an” and “the” and similar referents in thecontext of describing the invention (especially in the context of thefollowing claims) is to be construed to cover both the singular and theplural, unless otherwise indicated herein or clearly contradicted bycontext. The terms “comprising,” “having,” “including,” and “containing”are to be construed as open-ended terms (i.e., meaning “including, butnot limited to,”) unless otherwise noted. Recitation of ranges of valuesherein are merely intended to serve as a shorthand method of referringindividually to each separate value falling within the range, unlessotherwise indicated herein, and each separate value is incorporated intothe specification as if it were individually recited herein. All methodsdescribed herein can be performed in any suitable order unless otherwiseindicated herein or otherwise clearly contradicted by context. The useof any and all examples, or exemplary language (e.g., “such as”)provided herein, is intended merely to better illuminate the inventionand does not pose a limitation on the scope of the invention unlessotherwise claimed. No language in the specification should be construedas indicating any non-claimed element as essential to the practice ofthe invention.

While embodiments have been disclosed and described in detail, it isunderstood that various modifications and improvements thereon willbecome readily apparent to those skilled in the art. Accordingly, thespirit and scope of the present invention is not limited by theforegoing examples, but is better understood by the claims below.

What is claimed is:
 1. A percutaneously deliverable device for treatinga heart condition in a patient comprising: a first flange section havinga plurality of flange segments angularly spaced about a longitudinalaxis of the device, each flange segment of the first flange sectioncomprising two prongs meeting at a junction; and a second flange sectionhaving a plurality of flange segments angularly spaced about thelongitudinal axis of the device, each flange segment of the secondflange section comprising two elements meeting at a junction; whereineach of the flange segments the each of the first and second flangesections are adapted to fold in the same direction upon the device beingdrawn into an opening of a percutaneous catheter to assume a collapsedconfiguration in which the junctions of the flange segments of the firstflange section and of the second flange section are disposed distal totheir corresponding prongs.
 2. The device of claim 1, wherein the devicealso comprises a hub.
 3. The device of claim 2, wherein two or more ofthe flange segments of the first flange section each has a proximal endconnected to the hub.
 4. The device of claim 2, wherein the hub has atleast one of internal threads and external threads which are adapted toreleasably connect with complementary threads of at least one of adelivery device and a retrieval device.
 5. The device of claim 2,wherein the hub has a groove, the groove being adapted to cooperate witha collet of at least one of a delivery device and a retrieval device toform a releasable connection.
 6. The device of claim 2, wherein the hubhas a ball, the ball being adapted to cooperate with a claw device of atleast one of a delivery device and a retrieval device to form areleasable connection.
 7. The device of claim 2, wherein the hub has ac-shaped connector section, the c-shaped connector section being adaptedto cooperate with a complementary c-shaped connector section of at leastone of a delivery device and a retrieval device to form a releasableconnection.
 8. The device of claim 2, wherein the hub has an aperture,the aperture being adapted to receive at least one of a pin or a fingerof at least one of a delivery device and a retrieval device to form areleasable connection.
 9. The device of claim 1, wherein the devicecomprises a core section adapted to permit fluid flow therethrough. 10.The device of claim 1, wherein at least one flange segment of at leastone of the first and second flange sections has a first region having afirst thickness and a first width and a second region having a secondthickness and a second width wherein the respective magnitude of atleast one of the first thickness and the first width is different thanthe respective magnitude of, respectively, the second thickness and thesecond width so that the flexibility of the first region is differentfrom the flexibility of the second region.
 11. A reversibly collapsibledevice for treating a heart condition in a patient comprising a firstflange section, a second flange section, and a longitudinal axis,wherein each of the first and second flange sections comprise aplurality of separate, adjacent segments, each segment comprising twoprongs meeting at a junction, and is adapted to fold in the same axialdirection upon the device being drawn into an opening of a percutaneouscatheter to assume a collapsed configuration in which the junctions ofthe flange segments of the first flange section and of the second flangesection are disposed distal to their corresponding prongs.
 12. Thedevice of claim 11, wherein the device also comprises a hub.
 13. Thedevice of claim 12, wherein two or more of the flange segments of thefirst flange section each has a proximal end connected to the hub. 14.The device of claim 12, wherein the hub has at least one of internalthreads and external threads which are adapted to releasably connectwith complementary threads of at least one of a delivery device and aretrieval device.
 15. The device of claim 12, wherein the hub has agroove, the groove being adapted to cooperate with a collet of at leastone of a delivery device and a retrieval device to form a releasableconnection.
 16. The device of claim 12, wherein the hub has a ball, theball being adapted to cooperate with a claw device of at least one of adelivery device and a retrieval device to form a releasable connection.17. The device of claim 12, wherein the hub has a c-shaped connectorsection, the c-shaped connector section being adapted to cooperate witha complementary c-shaped connector section of at least one of a deliverydevice and a retrieval device to form a releasable connection.
 18. Thedevice of claim 12, wherein the hub has an aperture, the aperture beingadapted to receive at least one of a pin or a finger of at least one ofa delivery device and a retrieval device to form a releasableconnection.
 19. The device of claim 11, wherein the device comprises acore section adapted to permit fluid flow therethrough.
 20. The deviceof claim 11, wherein at least one flange segment of at least one of thefirst and second flange sections has a first region having a firstthickness and a first width and a second region having a secondthickness and a second width wherein the respective magnitude of atleast one of the first thickness and the first width is different thanthe respective magnitude of, respectively, the second thickness and thesecond width so that the flexibility of the first region is differentfrom the flexibility of the second region.
 21. A percutaneousdeliverable device adapted to be implanted into or retracted from, via acatheter, a patient's atrial septum, comprising: a first annular flangesection having a plurality of separate, adjacent flange segments, eachflange segment of the first annular flange section comprising two prongsmeeting at a junction; and a second annular flange section having aplurality of separate, adjacent flange segments, each flange segment ofthe first annular flange section comprising two prongs meeting at ajunction, wherein the flange segments of the first annular flangesection and the flange segments of the second annular flange section areconfigured to collapse in the same direction upon retraction by saidcatheter to assume a collapsed configuration in which the junctions ofthe flange segments of the first flange section and of the second flangesection are disposed distal to their corresponding prongs.
 22. Thedevice of claim 21, wherein the device also comprises a hub.
 23. Thedevice of claim 22, wherein two or more of the flange segments of thefirst flange section each has a proximal end connected to the hub. 24.The device of claim 22, wherein the hub has at least one of internalthreads and external threads which are adapted to releasably connectwith complementary threads of at least one of a delivery device and aretrieval device.
 25. The device of claim 22, wherein the hub has agroove, the groove being adapted to cooperate with a collet of at leastone of a delivery device and a retrieval device to form a releasableconnection.
 26. The device of claim 22, wherein the hub has a ball, theball being adapted to cooperate with a claw device of at least one of adelivery device and a retrieval device to form a releasable connection.27. The device of claim 22, wherein the hub has a c-shaped connectorsection, the c-shaped connector section being adapted to cooperate witha complementary c-shaped connector section of at least one of a deliverydevice and a retrieval device to form a releasable connection.
 28. Thedevice of claim 22, wherein the hub has an aperture, the aperture beingadapted to receive at least one of a pin or a finger of at least one ofa delivery device and a retrieval device to form a releasableconnection.
 29. The device of claim 21, wherein the device comprises acore section adapted to permit fluid flow therethrough.
 30. The deviceof claim 21, wherein at least one flange segment of at least one of thefirst and second flange sections has a first region having a firstthickness and a first width and a second region having a secondthickness and a second width wherein the respective magnitude of atleast one of the first thickness and the first width is different thanthe respective magnitude of, respectively, the second thickness and thesecond width so that the flexibility of the first region is differentfrom the flexibility of the second region.